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NATIONAL CENTER Series 11

For HEALTH STATISTICS Number 23

VITAL and HEALTH STATISTICSDATA FROM THE NATIONAL HEALTH SURVEY

Decayed,Missing, and

Filled Teeth in Adults

United States -1960 = 1962

Estimates of decayed, missing, and filled (DMF) teethby age, sex, race, and other maior demographic char-

acteristics, with a brief description of prevailingtrends.

DHEW Publication No. (HRA) 74-1278

U.S. DEPARTMENT OF HEALTH, EDUCATION, AND WELFAREPublic Health Service

Health Resources AdministrationNational Center for Health Statistics

Rockville, Maryland

.

,.,.—-. ..... . . .. .. . ..

Vital and Health Statistics-Series 11, No. 23

Reprinted as DHEW Publication No. (HRA) 74-1278

August 1973

First issued in the Public Health Service Publication Series No. 1000, February 1967

COOPERATIONOF THE BUREAU OF THE CENSUS

In accordance with specifications establishe’d by the Na-tional Health Survey, the Bureau of the Census, under a con-tractual agreement, participated in the design and selection ofthe sample, and carried out the first stage of the field interview-ing and certain parts of the statistical processing.

Library o/ Congress Catalog Card Number 66-62205

CONTENTSPage

Introduction ----------------------------------------------------------

Findings -------------------------------------------------------------Age and Sex--------------------------------------------------------Race-------------------------------------------------=------------

Other Demographic Variables -------------------------------------------hcome and Education -----------------------------------------------Race, hcome, and Education -----------------------------------------Place of Residence ---------- ---------------------------------------DMFTeeth in Young Adults 18-34 Years ofAge ------------------------

Summary -------------------------------------------------------------

References -----------------------------------------------------------

Detailed Tables -------------------------------------------------------

Appendix L The DentalExamination -------------------------------------Explanation of Findings ------------ ---------------------------------

Edentulous Arches -----------------------------------------------Smtusof Troth Spaces --------------------------------------------

Appendix II. Dem~raphic Terms ---------------------------------------

Appendix III. Statistical Notes ------------------------------------------~eSurvey Desi~---J ----------------------------------------------Reliabili~ ---------------------------------------------------------Sampling andMeasurementError -------------------------------------Expected Values ----------------------------------------------------Adjusted Values ----------------------------------------------------Tests of Si~ificance ------------------------------------------------Small Numbers -----------------------------------------------------Overestimation ofDMF Counts ---------------------------------------

1

345

56778

9

10

11

37373737

40

424242434646464747

IN THIS REPORT aye pyesented detailed national estimates of the num -bey of decayed, missing, and filled (DMF) teeth occurying in the adultpopulation of the United States. TYends appeavingamong white and Negvomen and women by vavious dernogyaphic featwres aye descyibed, and ina final section similay trends among yowng adults aged 18-34 years avebviefly discussed.

The estimates encompass approximately 91 million men and women (some20 million othe~s are excluded who still had one or more of thei~ ?aatuYalteeth. All of the estimates aye based on examinations conducted by theHealth Examination SuYvey duving- 1960-62 on a probability sample ofU.S. adults aged 18-79 yeays selected from the civilian ~opulation atlayge.

The numbey of DMF teeth increased rapidly and steadily with advancingage. At any given age, howevey, women had slightly moye DMF teeth thanmen of the same race, and white adults had substantially move than Ne -gYo adults of the same sex.

TYends in DMF teeth we ye also traced by family income, education, andspecified place of ~esidence. For instance, higher counts of DMF teethwere moye fyeqwent among people with gyeater income OYeducation andamong Yesidents of moye densely inhabited places. In addition, men andwomen living in the Northeast had significantly high cownts, and thoseliving in the %wth had significantly low ones.

Finally, ,?Yertdsencountered in the adult population as a whole weve alsofound to pyevail amongyoung adults 18-34 yeays old, suggesting that de-mographic differences in DMF teeth stem at least in part fvom corre-sponding variations in the incidence of dental decay.

SYMBOLS

Data not available ------------------------ ---

Category not applicable ------------------- . . .

Quantity zero ---------------------------- -

Quantity more than O but less than 0.05 ----: 0.0

Figure does not meet standards ofreliability orprecision ------------------ *

DECAYED, MISSING,

AND FILLED TEETH IN ADULTS

James E. Kelly, D. D.S., Lawrence E. Van Kirk, Jr., D.D.S., and Caroline C. Garst,Division of Health Examination Statistics

INTRODUCTION

During their lifetime, most Americans aredestined to fall victim to dental disease. Onsetoften commences in early childhood and frequently

‘ ceases only when there are no surviving teeth.Repeated attacks and the failure to receive promptand adequate dental care cause a vast but needlessloss of teeth among large numbers of men andwomen.

Among the more common conditions that re-sult from unstayed dental disease, none is moredisabling or disfiguring than the total loss of one’snatural teeth. In taking a nationwide inventoryamong adults, the Health Examination Survey foundthat an estimated 20 million men and women (18in every 100) had lost all of their natural teeth.The proportion of toothless persons increaseddrastically with advancing age, and by ages 65-79years every other man and woman had lost all ofhis or her teeth. 1

Teeth that are lost are almost always theresult of deep decay or advanced periodontal dis-ease. Undecayed or repaired teeth with healthysupporting structures will last until they areliterally worn away. Severe attrition of tooth sub-stance occurs only after extraordinary heavy andcontinuous use. It is rarely encountered in thiscountry, although at one time, when tobacco chew-ing was widely indulged in, it was frequently seen.Today dental decay and periodontal disease areunchallenged as the Ieading causes of tooth loss,the former in persons under 35 years of age andthe latter in older men and women. 2

Since early decay and all but the most ad-vanced periodontal disease can usually be ar-rested, it is difficult to understand why so manypeople take few if any measures to save theirteeth. Perhaps their attitude of seeming indiffer-ence is encouraged by the skill with which naturalteeth can be replaced by artificial ones. Underdifferent circumstances, it seems likely that toothremoval might be submitted to more grudginglyand recommended much less often than has beenthe custom. In any event, only about one in everytwo persons visits a dentist at least once a year;a large number of these visits are for extractionsand other surgery and, of course, for restoringpreviously extracted teeth. 3

Other estimates which clearly show the un-sparing onset of dental disease in the Nation atlarge have also been published by the Health Ex-amination Survey.1 Excluding the 20 million menand women whose only teeth were artificial, therewere 90 million who had on the average 18 teethwhich if not missing were either filled or in needof filling. Among these persons, moreover, werealmost 10 million who had lost all 16 teeth fromone jaw or the other.

Dental decay—a commonplace term in most20th century American households—is still notfully comprehended by those who have studied itmost thoroughly. Clinical studies and laboratoryexperiments have brought to light many of thedynamic events that are believed to lead to theorigination and development of a“carious lesion.Tooth decay is assuredly a complicated processinvolving diet, tooth susceptibility, and the pres-

1

ence of microorganisms to actuate and sustain it.However, no one really knows just how a cavitybegins, exactly how it progresses, or, for that

matter, all of the numerous interlacing factorsthat might be involved.

In the most widely accepted explanation, de-mineralization of the tooth’s outer enamel layerby acids is postulated. The acids are producedfrom various foodstuffs, especially sweet and

starchy ones, by the action of certain kinds of

bacteria commonly found in teeming numbers on

enamel surfaces.After the enamel has been deeply penetrated

and the underlying dentin bared, the inmost

structure of the tooth lies open to invasion. Den-tin, unlike enamel, incorporates a relativelylarge amount of organic matter (akmut 20 percent

by weight as compared with only about 1 percentfor enamel). The peculiar, tubelike organization

of its structural components permits the intrusionof bacteria and provides channels along whichthey can proliferate internally. The progressivedestruction of dentin is explained by the occur-

rence of two different chemical processes—ademineralization similar to that occurring in

enamel of the inorganic constituents by acid and adissolution of the organic material (matrix) byenzymes produced by encroaching microorgan-isms.

As to the occurrence of dental decay, two

observations are sufficiently evident that seldomare they seriously controverted: nearly everyonedevelops it at one time or another, and amongmost people the number of attacks continues to

mount with age. There is little ground for furthergeneralization because few surveys have carefullyand thoroughly examined the prevalence and dis-tribution of caries by any demographic charac-

teristic other than age. Some of the many surveys

conducted among children revealed a higher in-

cidence of decay in white girls than in white boys,and others which included both white and Negrochildren disclosed that the former usually hadmore decayed teeth than the latter.

Findings from two large surveys conducted

among adults suggest that the variation of DMFteeth by sex and race in children carries overinto adulthood. In both of these studies, wornenconsistently had slightly more decayed, missing,and filled teeth than men; and in one white men

and women had sharply more DMF teeth than did

comparable Negro adults. 4’5It is surprising that comparatively little is

known about the occurrence of a disease which un-ceasingly harasses so many people. Ironically,much more might have been learned had it notbeen for the exciting discovery more than a quarterof a century ago that an unknown ingredient con-tained in the drinking water of some communities

increases man’s immunity to tooth decay. Fromthat mom ent on the imagination and resources ofepidemiological research were largely engaged

in studies which eventually revealed fluoride as

the ingredient and established a safe and effective

method of improving dental health. With betterteeth at stake for millions of persons, it is nowonder that many other areas of dental epidemi-

ology were relatively neglected until quite re-cently.

This report contains national estimates of thenumber of decayed, missing, and filled teeth byvarious demographic characteristics. Some of theestimates by age, sex, and race appeared in a

previous report, 1 but others, including ‘those byplace of residence, family income, and educationalattainment, are presented here for the first time.

The estimates embrace some 91 million dentulousadults who, having at least one extant tooth, werestill liable to tooth loss.

The estimates are based on findings obtainedduring 1960-62 from the examination of 6,672 menand women aged 18-79 years. By virtue of the

statistical principles which determined their se-lection, the sample persons represented within a

known range of probability the much larger popu-lation of which they were a part—approximately

111 million U.S. adults in the civilian, norlinstitu-tional population. A description of the selection

of sample persons, a description and an assess-

ment of the dental examination, and an explana-

tion of the procedure for deriving national esti-mates have previously been published. *~” 7

The mouth and teeth of each sample personwere examined by one of five dentists who had

been trained beforehand to perform the exami-

nation by a prescribed procedure. Radiographsof the teeth were not taken. The procedure alsodeparted in other respects from the examination

routinely given to many patients who seek dental

care: teeth were not dried or isolated, oral debris

2

and calculus were not removed prior to observa-tion, and tooth surfaces were not probed unlessthe’ examiner saw an indication of the presenceof covert decay. To further increase agreementboth within and between examiners, questionableor borderline conditions were purposefully notreported.

While these provisions heightened the com-parability of findings as they were intended to do,they also lessened the sensitivity of the examina-tion. As a result, many findings are conservativein comparison with what would be obtained byclinical evaluation. For example, defectivelyfilled, nonfunctional, and especially decayed teethare systematically underestimated from a clinicalviewpoint while, conversely, complementarycounts of normal and functional teeth are over-estimated. Other estimates, however, such as thenumber of filled and missing teeth are derivedfrom objective counts which are highly comparableby any standard.

In many places within this report the dentalcondition of particular groups of men and womenis briefly described by citing the mean number ofdecayed, missing, and filled (DMF) teeth enumer-ated among them. This calculated value is calledtheir DMF index. For anyone at any age, DMFteeth can be defined as the sum total of permanentteeth that are decayed, filled, and either missingor indicated for extraction. In younger adultswho lose relatively few teeth from any cause otherthan decay, DMF teeth accurately measure thenumber of teeth that have been attacked by decayat least once. Thus, differences between DMFindexes of groups of young persons whose age isthe same reflect relative variations in the rate atwhich their teeth have been attacked. If, for ex.ample, the DMF indexes of two groups of men andwomen aged 18-24 years are 8 and 16 teeth, re-spectively, it can reasonably be inferred that thecaries attack rate has been twofold greater amongwomen than among men even though the numberof times each tooth had been attacked is not takeninto account.

On the other hand, older adults often lose manyteeth from severe periodontal disease which pro-gressively destroys the structures supporting theteeth in the jaw. Among older men and womenwhose missing teeth may never have had decay,the DMF index merely provides a convenient sum-mation of the lifetime toll of all dental disease.

100

80 —

—

LOz0m 60 —

Hn

k

i-Zu$ 40 —

f

20

I

o~20 30 40 50 60 70 80

AGE IN YEARS

Fiaure 1. Percent of Dersons with at least onenatural tooth, by age.

DMF counts in this report are based on 32teeth. Since unerupted third molars were notidentified, they were included along with extractedmolars in counts of missing teeth. This procedureresulted in overestimates of DMF counts as ameasure of the impact of dental disease, especiallyfor younger adults, many of whom have uneruptedthird molars (see Appendix 111).

Based on exam’inations, approximately 20million men and women had lost all of theirnatural teeth. Their exclusion from the estimatesthat follow resulted in a diminishing proportionof persons within each older age group (fig. 1)and, within specified age ranges, proportionatelyfewer white persons than Negroes and fewerwomen than men.

FINDINGS

A vast majority of the 91 million men andwomen who were still at risk to tooth loss showedabundant evidence of prior attack by dental dis-ease. More than half of them had more than 18decayed, missing, and filled teeth; and a quarter

3

had as many as 24 or more (table 1). In sharpcontrast, it was the exceptional person (about 1 in160) who possessed a full complement of 32 teeth,

none of which was either filled or decayed. Re-flecting the exceedingly high rate of attack towhich they had been subjected, men and womenof all races averaged 17.9 DMF units per person—an aggregate comprising 1.4 decayed, 9.4 lmissing,

and 7.0 filled teeth (table 5).Each of the DMF components (decayed, miss-

ing, and filled teeth) was more or less concen-trated in segments of the population which, al-though containing large numbers of men andwomen, were nonetheless proportionately small(tables 2-4). For instance, 1 in every 5 personshad 15 missing teeth or more, all of which ac-counted for nearly half of the total number ofmissing teeth. Similarly, every other man and

woman had six or more filled teeth, so that fully

90 percent of all filled teeth were encounteredin only half of the population. In marked contrast,

a quarter of the population had no filled teeth.Finally, decayed teeth, which include those with

faulty fillings as well as those with untreated

cavities, were even more narrowly distributed.

While 1 in every 2 men and women had no de-

cayed teeth, the 1 in every 10 who had any at allhad more than six. In other words, one-half

of the total number of decayed teeth occurred inone- tenth of the population.

Age and Sex

DMF teeth amassed rapidly with lengtheningexposure to the risk of disease. From a low of13.4 and 14.1 for the youngest men and women,

30

r

25

: 20

JJ

) 15[

1D

> 10

5

018-24

MEN

AGE GROUP

I

18-24

‘s

WOMEN 1

45-54 55-64

AGE GROUPS

Figure 2. Mean number of decayed, missing, and f i1led teeth among dentulous men and women, by age.

4

20.0 I I

16.0

4.0

0.0

MEN WOMEN

I

I

White Negro White Negro

ihti

Figure 3. Mean number of decayed, missing, andfilled teeth among dentulous white and Negromen and women.

respectively, mean counts climbed without faltertoahigh ofabout 25 per person among the oldestmen andwomen (table 5). The uninterrupted riseresulted from the increasing tooth loss whichaccompanied aging. By contrast, the number ofdecayed teeth declined gradually, as did filledteeth after reaching ahighofabout8 per personamong menandwomen aged 25-44 years (fig. 2).

Comparative counts of decayed, missing, andfilled teeth suggest that women are slightly moreprone to dental disease than men. The mean num-ber of DMF teeth per man and woman was 17.2and 18.5, respectively. The difference by sex,although never large, recurred consistently. With-in each of the various age groups, women usuallyhad one or two more DMF teeth than men.

Race

‘The DMF index for white adults was half againas high as that for Negro adults, with an averageper person of 18.7 and 12.2, respectively (tables

6 and 7). This sharp difference was the result ofa much larger number of filled teeth among whiteadults than among Negro adults—7.8 as comparedwith ordy 1.5—and of a sIight excess in the num-ber of missing teeth among white adults—9.6 ascompared with 8.7. On the other hand, Negroadults averaged somewhat higher quantities ofdecayed teeth (fig. 3).

Trends by both age and sex were remarkablyconsistent. Women without exception had higherDMF counts than men of the same race and age.

The mean number of DMF teeth for all whiteand Negro men and women appearfin table 8. Theinclusion of edentulous persons elevates indexvalues by approximately one-eighth but entailslittle or no appreciable effect upon differentialsexisting by age, sex, and race.

OTHER DEMOGRAPHIC VARIABLES

Many of the more common dental conditionshave frequently been found to vary significantlyin prevalence and severity by levels of family in-come and education as well as by age, sex, andrace. For example, the Health Examination Sur-vey found that periodontal disease in adults wasinversely related to rising levels of education andfamily income. $ In the remainder of this reportmen and women whose dental conditions are beingdescribed have been classified by specified rangesof income and education; in addition, they havebeen classified by specified place of residence.

After the population was grouped, any differ-ences which appeared in mean DMF teeth perperson among the various groups were examined.For example, mean DMF counts for white andNegro adults whose family income was within oneof five different income ranges were examined todetermine whether the mean count within onerange differed significantly from that withinanother. Allowance was made for differences inthe age and sex distribution of persons composingthe various groups since DMF teeth have alreadybeen shown to vary importantly by both of these .characteristics.

Expected values were calculated by weightingage- and sex-specific mean DMF counts for thetotal U.S. population by the age-sex distributionof respective groups. Actual and expected valuesmay occasionally be expected to differ by chance.But when the difference is not statistically signif-

5

icant, it can generally be assumed that differ-ences between DMF indexes for component age-sex groups fluctuated randomly.

Because of the relatively limited number of

sample persons, sampling variability for specificage and sex groupings was usually quite large.It is for this reason that summary comparisonsof actual and expected mean counts were preferred

to a comparison of mean age-specific counts.

Income and Education

The amount of yearly income earned by a

family was directly associated with the number of

DMF teeth its adult members had. Men and womenin families whose annual incomes were high tendedto have more DMF units than those in familieswith low incomes (tables 9-12). For example,

men of all races whose yearly family income ex-

ceeded $9,999 had 19.0 DMF teeth per person, butthose with incomes of less than $2,000 averagedonly 15.3 (table 9).

Exactly the same trend in DMF teeth reoc-

curred with education (table 13). Women of all

races with less than 5 years of schooling had 15.0

DMF teeth per person. By contrast, those who hadcompleted 1 year or more of college had 19.3.

The trend by education, like the one by income,

is more pronounced among white adults than

among Negro men and women; in fact, the onlysemblance of the trend among the Negro popu-lation was the one by income among women.

The rate of edentulous persons in the U.S.

population has been found to decrease sharplywith increasing income and education. 9 The in-

clusion of edentulous men and women in the above

estimates significantly reduced but did not entirelyeliminate the numerical differences in DMF teeth

that were obtained. However, the DMF indexamong adults 18-79 years of age is not a reliable

measure of dental caries activity nor an indicatorof good or bad dental health but merely a concisedescription of dental findings.

Income and education were significantly as-

sociated not only with the number of DMF teeth

but, to an even greater extent, with their propor-tionate composition (tables 10-12, 14- 16). For

example, the mean number of filled teeth in

women rose abruptly from 1.4 among those with

60 –

MEN WOMEN

- 4,0:c!:%; 2,0 -

1.5?: 0.9

c

j 00

Lz>

~ -2.0 ~J>~J

J

:-4.0

S -4.3

-4,0

-6.0-Under 5-8 9-12 13+ Under 5-.9 9-12

513+

years years years 5 years years yearsyears years

EDUCATION

Figure !. D i fferences between actual and expected

mean number of decayed, missing, and fil led (DMF)

teeth among dentulous men and women. by edu-,.cat i on.

the least education to 11.2 among those with T6emost (table 16). Both decayed and missing teethfollowed counter trends which, however, were tooweak to offset the margin of difference resultingfrom filled teeth. Again, citing women by educa-tion as an example, those in the topmost grouphad 4.3 more DMF teeth than those in the lowest.Although the latter had many more decayed plusmissing teeth than the former (13.6 as comparedwith 8.1), they also had many fewer filled teeth—

only 1.4 as compared with 11.2. The outcome wasa net increase in DMF teeth with rising incomeand education. Thus, adults with higher income or

education had more DMF teeth than less advan-taged men and women, but judging from the greater

number of teeth they had and the smaller number

of decayed ones, their dental condition was none-theless the better.

Trends in DMF teeth did not arise because

there were relatively more older persons within

6

MEN

—-.“

Ihder $2,000- $4,000- ZOOO-$29000 $3,999 $6,999 $

9,999 $WxM+

WOMEN

1.5

FAMILY INCOME

Under $2,000- $4,000-$~g- $Io,ooot

$2,000 $3,999 $6,999 ,

Figure 5. Differences between actual and expected mean number of decayed, missing, and filled (DMF)teeth among dentulous men and women, by family income.

each higher income and educational group. Onthecontrary, bothtrends aresomewhatmoreapparentin the differences between actual and expectedcounts than they are in actual counts (figs. 4 and5, tables 9-16).

DMF teeth continued to vary in number bysex. Throughout the various ranges ofincomeandeducation, white and Negro women almost alwayshad more DMFteeth thanmenofthe same race.

In figure 6, differences between actual andexpected numbers ofDMF teeth by income, afteradjustment for education, are shown. Thetrendinnumbers, although reduced inmagnitude, wasun-changed in direction. Adjustment for educationlowered the variance in mean counts attributableto income to approximately athirdof its formervalue. In short, both income and education appearto be independently correlated with DMF teeth.

Race, Income, and Education

Variations in income and education fail toexplain the wide difference in DMF teeth observedby race. Within any of the levels of income andeducation shown in table 17, white men continueto have a substantially higher index than Negromen as do white women in comparison with Negrowomen. Because proportionately few Negro adultshad family incomes exceeding $6,999 per year oreducation beyond high school, mean values couldnot meaningfully be compared at these levels.

Place of Residence

Estimates of the mean number of DMF teethin white and Negro men and women dwellin”g inthree broad regions of the United States-the

7

MEN wOMEN

z.

~ 1~ ~1.1

; 0.6 0.7.?

0.70.2

0.6

? 0.0ww1-IL -0.82 -1.2z -2,0 -1.5

-1.9

IiiE -4.0LIL Under $2,000- $4,000-

:;:9:- $10,000 +Under $2,000- $4,000-

$7’000- $10,000+= $2,000 $3,999 $6,999 , $2,000 $3,999 $6,999 $9,999

FAMILY INCOME

Figure 6. Differences between actual and expected mean number of decayed, missing.and filled (DMF) teeth

among dentulous men and women, by family income adjusted for education.

Northeast, South, and West—appear intable 18.In the Northeast, itwill be noted, adults had con-sistently higher estimates than were expected,whereas in the South they had consistently lowerones. Moreover, differences betweentheobservedand expected means are statistically significantfor every group except Negrowomenin theNorth-east. Estimates for adults who lived in the Westshowed, by contrast, no significant regionalvari-ation.

Estimates of DMI? teeth were also obtainedby place description, population size, and urban-rural residence (tables 19-21). With remarkablyfew exceptions, white men and women from moredensely inhabited areas had higher numbers ofDMF teeth than persons from areas that are lessdensely peopled.

DMF Teeth in Young Adults

18-34 Years of Age

The trends in DMF teeth which have beendescribed evolved with a consistency that wassignificant not only by age, sex,and race but alsoby income, education, and place of residence.Each demographic variable had an association

which was its own inthesensethatit was not fullyerased by controlling for others. It should againbe stressed that variations in DMF teeth in theadult population do not necessarily imply the onsetof more or less dental disease nor do they implythe presence of better or worse dental health.Moreover, any attempt to explain the factorsunderpinning the pattern that unfolded is fore-stalled because teeth extracted due to decay can-not be excluded from those lost because of severeperiodontal disease. To illustrate the insurmount-able problem this imposes, many men and womenlose teeth previously neither filled nor decayedwhen periodontal disease reaches the stage ofseverity at which extraction is the most practicalrecourse. Many others with equally severe diseasehave fewer missing teeth simply because they havenot sought the care which under the circumstancesis appropriate. Thus, the exasperating but in-eluctable question which arises is whether peopleobtain more care because they have more dentaldisease or whether they only ostensibly have moredisease (higher DMF counts) because they havesought relatively more care.

The data on hand can perhaps provide someinsight into the sources of the developing trends.In tables 22-24, estimates of DMF teeth in young

8

adults aged 18-34 years are singled out forcloser attention. If the mmepatternprevailsh ereas in the population as a whole, it will suggestthat DMl? differentials arise at least in part fromvariations in susceptibility to dental decay.

In table 22 it will be noted that the trendsby sex and race have gained an early but firmfoothold. Young women already have slightly moreDMF teeth than men of the same race, and whiteadults have many more than Negro adults. Alsoin effect in the white population (tables 23 and24) are the trends by income and education, withDMF counts increasing generally with risingfamily income and strikingly with improving ed-ucation. For example, white men who had com-pleted less than 5 years of school averaged about8 DMF units per person, but those who had com-pleted 1 year or more of college had twice asmany.

The differences in the number of DMF teethby income and education occur largely because ofthe variation in numbers of filled teeth. On theother hand, comparatively little difference in thenumber of missing teeth is associated with any ofthe variables. Decayed teeth, which vary onlyslightly by sex, decline in number with increasingincome and education. As in the entire white adultpopulation, trends in the number of missing anddecayed teeth are not sufficiently strong to over-take the opposing trend in filled teeth.

If trends in DMF teeth among adults do re-flect variations in susceptibility to decay, and itappears that they indeed do, the question next inturn is why these variations follow certain linesof demographic distribution. It must not be over-looked that even the increments in DMF teethwhich occur with age are less clear and simplethan they might seem; they reflect, for example,not only length of exposure to disease but, in ad-dition, whatever variation happens in the degreeof relati%e immunity or susceptibility possessedby individuals. In short, the true source of thenumerical variation in DMF teeth among youngeradults must be sought among the bewilderinglynumerous elements at interplay in the diseaseprocess that causes decay. These factors, intri-cately linked with diet, tooth susceptibility, andthe action of oral bacteria, occur on a plane wherethe survey has little or no information to bringto bear in disclosing them.

WVWARY

The widespread prevalence of dental diseasein the U.S. population at large is nowhere moreclearly revealed than in the number of decayed,missing, and filled teeth enumerated among adults.While nearly 20 million men and women no longerpossessed any natural teeth, approximately 91million others had an estimated 17.9 DMF teethper person—a total consisting of 1.4 decayed,9.4 missing, and 7.0 filled teeth.

National estimates of decayed, missing, andfilled (DMF) teeth are based on the examinationin 1960-62 of a probability sample comprising6,672 persons from the civilian, noninstitutionalU.S. population 18-79 years of age. The estimatespresented here include only the 91 million menand women who, owing to the presence of at leastone natural tooth, continued at risk to tooth loss.

DMF teeth accumulated rapidly with advanc-ing age. From a low of 13.4 and 14.1 among theyoungest men and women, respectively, meancounts increased within each successive age groupuntil they reached approximately 25 per personfor both men and women aged 75-79 years. Thetrend with age resulted from an unremitting lossof teeth. By contrast, decayed teeth slowlydwindled in number, as did filled teeth after theyreached a maximum of about 8 per person amongadults 25-44 years of age.

Proportionately half again as many DMF teethwere counted among white adults as among Negroadults, with an average per person of 18.7 and12.2, respectively. White adults had, on the onehand, many more filled and slightly more miss-ing teeth but, on the other, fewer decayed ones.Throughout the comparison by race, DMF countswere consistently higher for women than for menof the same race and for white men and womenthan for Negro men and women.

The number of DMF teeth was significantlyrelated to family income and education. Men andwomen with greater means or higher schoolingusually had more DMF teeth than poorer personsor persons with less education. The trends by in-come and education were more pronounced in thewhite than in the Negro population; and amongpersons whose income or education was the same,women had more DMF teeth than men and whiteadults had sharply more than Negroes.

9

DMF teeth also were found to vary in numberby place of residence. For instance, white andNegro men and women living in the Northeast hadmore DMF teeth than those living elsewhere; bycontrast, those in the South had fewer. Among thewhite population, residents of more densely pop-ulated areas usually had higher count# than menand women residing in less dense areas.

Variations in the number of DMF teeth bysex, race, education, and income prevailed notonly in the adult population as a whole but alsoin younger adults aged 18-34 years among whom

such variation signifies a difference in the rate atwhich their teeth have been attacked by decay.Thus, it appears that women are slightly moreprone to dental decay than men, persons withhigher income or education more prone thanpoorer or less schooled persons, and white adultssubstantially more prone than Negro adults. Insum, a variance in the attack rate of dental decayappears to be at least partly responsible fordemographic variations in the number of DMFteeth observed in the adult population of theUnited States.

REFERENCES

lNatjona[ Center for Health Statistics: Selected dental

findings in adults hy age, race, and eex. Vital and Hca2thStatistics. PHS Fub. No. 1000-Series 11-No. 7. Public HealthService. Washington. U.S. Government Printing Office, Feb.

1965.

2American Dental Association, Bureau of “Economics and

Statistics: Survey of needs for dental care, II, dental needeaccording h age and sex of patients. J. Am. Dent. d. 46:200,Feb. 1953.

3National Center for Health Statistics: Dental vieits, time

interval since last visit. Vital and HeaZth Statistics. PHS Pub.

No. 1000-Series 1O-NO. 29. Public Health Service. Washington.L1.S. Government Printing Office, Apr. 1966.

4Hollander, F., and Dunning, J. M.: A study by age and

sex of tbe incidence of dental caries in over 12,000 pereons.

J. Dentures. 16:43-60, Feb. 1939.

5Commission on Chronic Illness: Chronic /?tn.ess in theUnited Statee, Vol. IV, Chr’onic Illness in a La?ge City. Cam-

bridge, Mass. Harvard University Press, 1957. ch. 5.

6National Center for Health Statistics: Plan and initial

program of the Health Examination Survey. Vital and HealthStatistics. PHS Pub. No. 1000-Series l-No. 4. Public Health

Service. Washington. U.S. Government Printing Office, July

1965.

7National Center for Health Statistics: Cycle I of the

Health Examination Survey, eample and response. Vita? andHealth Statistics. PHS Pub. No. 1000-Series 11-No. 1. Pub-

lic Health Service. Washington. U.S. Government Printing

Office, Apr. 1964.

8National Center for Health Statistics. Periodontal dis-

ease in adults. Vita? and .Health Statistics. PHS Pub. No.

1000-Series 11-No. 12. Public Health Service. Washington.

U.S. Government Printing Office, Nov. 196.%

‘U.S. National Health Survey: Loss of teeth. Health Sta-

tistics. PHS Pub. No. 584-B22. Public Health Service.Washington. U.S. Government Printing Office, Sept. 1960.

000

10

Table 1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.

15.

16.

17.

18.

19.

Numberteeth:

DETAILED TABLES

Page

of dentulous men and women, by number of decayed, missing, and filled (DMF)United States, l96O-62----------------------------------------------------- 13

Nu;;e;2 of dentulous men and women, by number of decayed teeth: United States,----------------------------------------------------------------------------

Nuh&e;20f dentulous men and women, by number of missing teeth: United States,-----------------------------------------4---------------------------------

Nu&e;2 of dentulous men and women, by number of filled teeth: United States,------------------------ ---------------------------------------------------

Mean number of decayed, missing, and filled teeth among dentulous adults, by sexand age: United States, l96O-62---------------------------------------------------

Mean number of decayed, missing, and filled teeth among dentulous white adults, bysex and age: United States, l96O-62-----------------------------------------------

Mean number of decayed, missing, and filled teeth among dentulous Negro adults, bysex and age: United States, l96O-62-----------------------------------------------

Mean number of decayed, missing, and filled (DMF) teeth among adults, includingedentulous persons, by race, sex, and age: United States, 1960-62-----------------

Actual and expected mean number of decayed, missing, and filled (DMF) teeth amongdentulous men and woman, by race and family income: United States, 1960-62-------

Actual and expected mean number of decayed teeth among dentulous men and women,, byrace and family income: United States, 1960-62------------------------------------

Actual and expected mean number of missing teeth among dentulous men and women, byrace and family income: United States, 1960-62------------------------------------

Actual and expected mean number of filled teeth among dentulous men and women, byrace and family income: United States, 1960-62------------------------------------

Actual and expec~ed mean number of decayed, missing, and filled (DMF) teeth amongdentulous men and women, by race and education: United States, 1960-62------------

Actual and expected mean number of decayed teeth among dentulous men and women,by race and education: United States, 1960-62-------------------------------------

Actual and expected mean number of missing teeth among dentulous men and women, byrace and education: United “States, 1960-62----------------------------------------

Actual and expected mean number of filled teeth among dentulous men and women, byrace and education: United States, 1960-62----------------------------------------

Mean number of decayed, missing, and filled (DMF) teeth among dentulous white andNegro men and women, by family income and education: United States, 1960-62-------

Actual and expected mean number of decayed, missing, and filled (DMF) teeth amongdentulous men and women, by race and region: United States, 1960-62---------------

Actual and expected mean number of decayed, missing, and filled (DMF) teeth amongdentulous men and womeqby race and place description: United States, 1960-62-----

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

11

DETAILED TABLES—Con.

Page

Table 20. Actual and expected mean number of decayed , missing, and filled (DMF) teeth amongdentulous men and women,by race and population-size group: United States,1960-62-- 32

21. Actual and expected mean number of decayed, missing, and filled (DMF) teeth amongdentulous men and women,by race and urban-rural residence: United States,1960-62-- 33

22. Mean number of decayed, missing, and filled (DMT) teeth among dentulous white andNegro men and women 18-34 years of age: United States, 1960-62-------------------- 34

23. Mean number of decayed, missing, and filled teeth among dentulous white men andwomen 18-34 years of age, by family income: United States, 1960-62---------------- 35

24. Mean number of decayed, missing, and filled teeth among dentulous white men andwomen 18-34 years of age, by education: United Statesj 1960-62-------------------- 36

12

Tablq 1. Number of dentulous men and women, by number of decayed, missing, and filled (DMF)teeth: United States, 1960-62

Number of decayed,missing,and filled teeth

Total------------------------

1---------------------------- -------

2-----------------------------------

3----------------------------------

4----------------------------------

5----------------------------------

6----------------------------------

8-----------------.----------------

10--------- ------------------------

11---------------------------------

12---------------------------------

13---------------------------------

15--------------------------- ------

Men IWomen

Number inthousands

43,933

331

380

480

949

834

838

968

1,093

978

1,320

1,652

1,508

1,504

1,741

1,552

1,625

46,763—

234

333

265

434

1,008

732

835

842

1,007

1,203

1,237

1,207

1,372

1,358

1,500

1,840

Number of decayed, missing,and filled teeth

16--------------------------

17--------------------------

18--------------------------

19--------------------------

20--------------------------

21--------------------------

22--------------------------

23--------------------------

24--------------------------

25--------------------------

26--------------------------

27--------------------------

28--------------------------

29--------------------------

30--------------------------

31--------------------------

32--------------------------

TNumber inthousands

2,116

1,880

1,836

1,932

1,769

1,968

1,897

1,878

2,227

1,811

1,714

1,249

1,030

950

597

513

833

1,879

2,028

2,148

2,212

2,344

2,139

1,859

2,382

2,675

2,795

2,604

1,,928

1,568

767

626

547

858

NOTE: Filled teeth include only teeth with satisfactoryfillings. Decayed teeth includenotonly teeth with caries but also filled teeth with carioua lesions or defective fillings.Hissingteeth include both missing and nonfunctionalteeth. DMF is the total of these three categories.Third molars are included in the count.

Table 2. Number of dentulous men and women, by number of decayed teeth: United States, 1960-62

Number of decayed teeth

Total------------------------

o----------------------------------

l----------------------------------

2----------------------------------

3----------------------------------

4----------------------------------

5--------------------------------.-

6-------.--------------------------

7----------------------------------

8----------------------------------

9----------------------------------

10---------------------------------

11---------------------------------

12---------------------------------

13---------------------------------

14---------------------------------

15---------------------------------

I

~

Number inthousands

43,952

22,046

7,963

4,421

3,118

1,897

1,460

893

699

548

388

197

115

63

41

56

14

46,759—

24,984

8,020

4,913

2,788

1,833

1,348

899

626

493

268

186

95

68

75

26

66

Number of decayed teeth

16-------------------------

17-------------------------

18-------------------------

19-------------------------

do-------------------------

21-------------------------

22-------------------------

23-------------------------

24-------------------------

25-------------------------

26-------------------------

27-------------------------

28-------------------------

29-------------------------

30-------------------------

31-------------------------

32-------------------------

Men

Number inthousands

23

10

14

11

31

15

NOTE : Filled teeth include only teeth with satisfactory fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious lesions or defective fillings. Missingteeth include both missing and nonfunctional teeth. DMF is the total of these three categories.Third molars are included in the count.

Table 3. Number of dentulous men and women, by number of missing teeth: United States, 1960-62

b

Number of missing teeth

Total ------------------------

o----------------------------------

1------------------------- ---------

2-------------------------------- --

4---------------------------- ------

5---------------- ----------------- -

6-.---------------------- -----------

7-----------------------------------

8---------------------------- ------

9----------------------------------

10------------------ ---------------

11----------------------------- ----

12------------------- -----.--------

13---------------------------------

14---------------------------------

15---------------------------------

Men I Women

Number inthousands

43,954

1,773

1,869

2,212

3,563

4>969

3,694

3,223

2,797

2,444

2,040

2,052

1,379

1,236

1,213

732

717

46,760

1,107

1,189

2,200

2,760

6,343

4,498

3,527

3,208

2,743

2,030

1,927

1,444

1>488

1,178

869

843

Number of missing teeth

16-------------------------

17-------------------------

18-------------------------

19-------------------------

20-------------------------

21-------------------------

22-------------------------

23-------------------------

24-------------------------

25-------------------------

26-------------------------

27-------------------------

28-------------------------

29-------------------------

30-------------------------

31-------------------------

32-------------------------

Men Women

Number inthousands

686

667

413

654

457

340

599

525

748

700

463

361

266

268

229

292

373

709

619

646

512

507

647

797

721

1,208

886

1,008

312

292

83

177

94

188


15

Table 4. Number of dentulous men and women, by number of filled teeth: United States, 1960-62

Number of filled teeth

Total------------------------

o ------ -------------------- - --- ----

1- - --- ----------------- -------- ----

2----------------------------------

3----------------------------------

4----------------------------------

5-----------------------------------

6..-------------------------..-------

7----------------------------------

8----------------------------------

9----------------------------------

10---------------------------------

11---------------------------------

13---------------------------------

14---------------------------------

15---------------------------------

zNumber inthousands

43,950

11,261

2,806

2,939

2,205

1,680

2,066

1,733

1,999

1,493

1,632

1,877

1,673

1,520

1,577

1,451

1;359

46>760—

10,524

2,993

2,486

2,119

1,815

1,446

2,029

1,674

1,598

1,817

1,665

1,921

2,411

1,770

1,948

1,791

Number of filled teeth

16-------------------------

17-------------------------

18-------------------------

19-------------------------

20-------------------------

21-------------------------

22-------------------------

23-------------------------

24-------------------------

25-------------------------

26-------------------------

27-------------------------

28-------------------------

29-------------------------

30-------------------------

31-------------------------

32-------------------------

EEiENumber inthousands

1,003

895

716

656

51’4

341

145

193

78

46

59

33

,.

!.

,.

..

1,431

1,281

1,267

1,061

679

445

362

102

113

12

NOTE : Filled teeth include only teeth with satisfactory fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious lesions or defective fillings, Missingteeth include both missing and nonfunctional teeth. DMF is the total of these three categories.Third molars are included in the count.

16

Table 5. Mean number of decayed, missing, and filled teeth among dentulous adults, by sex andage: United States, 1960-62

Sex and age

Both sexes

Total, 18-79 years --------------------------------------

Men—

Total, 18-79 years --------------------------------------

18-24 years---------------------------------------------------

25-34 years---------------------------------------------------

35-44 years-------------------------------------------y-------

45-54 years---------------------------------------------------

55-64 years---------------------------------------------------

65-74 years ---------------------------------------------------

75-79 years ---------------------------------------------------

Women

Total, L8-79 years--------------------------------------

18-24 years---------------------------------------------------

25-34 years ---------------------------------------------------

35-44 years---------------------------------------------------

45-54 years---------------------------------------------------

55-64 years---------------------------------------------------

65-74 years---------------------------------------------------

75-79 years---------------------------------------------------

rotalDMFteeth

17.9

17.2

13.4

15.8

17.2

18.0

20.4

22.3

24.4

18.5

14.1

17.5

18.8

19.6

21.9

22.8

25.0

)ecayed

1.4

.1.5

2.2

1.8

1.3

1.3

1.1

0.8

0.7

1.4

2.0

1.6

1.3

1.1

0.8

0.5

0.7

Missing

9.4

9.2

4.6

6.2

8.1

10.9

14.7

18.1

21.7

9.6

5.0

7.5

9.2

11.5

14.8

16.8

20.1

Filled

7.0

6.5

6.6

7.8

7.8

5.8

4.6

3.5

2.0

7.5

7.2

8.4

8.3

7.0

6.3

5.5

4.3

NOTE: Filled teeth include only teeth with satisfacto~ fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious lesions or defective fillings. Missingteeth include both missinz and nonfunctional teeth. DMF is the total of these three cate~ories.Third molars are included In the count.

17

Table 6. Mean number of decayed, missing, and filled teeth among dentulous white adults, by aexand age:‘United States, 1960-62 -

Sex and age

18-24

25-34

35-44

45-54

55-64

65-74

75-79

18-24

25-34

35-44

45-54

55-64

65-74

75-79

Total

Total

Both sexes

18-79 years--------------------------------------

Men—

18-79 years--------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

Women

Total, 18-79 years--------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

TotalDMFteeth

18.7

18.1

14.1

16.8

18.4

18.8

21.5

22.7

24.4

19.2

14.8

18.4

19.5

20.4

22.5

23.4

25.0

Decayed

1.3

1.5

2.1

1.8

1.3

1.3

1.1

0.7

0.8

1.2

1.9

1.4

1,1

1.1

0.7

0.6

0.7

Iissing

9.6

9.4

4.7

6.5

8.4

11.0

15.2

18.2

21.5

9.7

5.(2

7.5

9.1

11.5

14.‘7

16.9

19.2

Filled

7.8

7.3

7.3

8.5

8.7

6.5

5.2

3.8

2.2

8.3

7.9

9.5

9.3

7.9

7.1

6.0

5.1

NOTE : Filled teeth include only teeth with satisfactory fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious leaions or defective fillings. Missingteeth include both missin~ and nonfunctional teeth. DMF is the total of these three categories.Third molars are included k the count.

18

Table 7. Mean number of decayed, missing, and filled teeth among dentulous Negro adults, by sexand age: United States, 1960-62

Sex and age

18-24

25-34

35-44

45-54

55-64

65-74

18-24

25-34

35-44

45-54

55-64

65-74

Total, 18-79

Total, 18-79

Both sexes

years--------------------------------------

Men—

years--------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

Women

Total, 18-79 years--------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

years---------------------------------------------------

TotalDMFteetk

12.2

11.3

8.1

8.4

9.2

13.6

15.1

19.0

13.0

9.2

12.3

13.8

13.7

16.8

14.6

Decayed

2.1

1.8

2.6

1.9

1.7

1.6

1.6

1.8

2.3

3.0

3.2

2.0

1.6

1.3

0.4

Missing

8.7

8.3

4.7

4.8

6.2

10.8

12.6

16.8

9.0

4.6

7.1

9.7

10.5

14.7

13.9

Filled

1.5

1.2

0.8

1.8

1.3

1.2

1.0

0.3

1.7

1.7

2.0

2.2

1.6

0.8

0.2

NOTES: Where categories are not listed for a specific race-sex group, the sample size was toosmall for reliable estimates to be presented.

Filled teeth include only teeth with satisfactory fillings. Decayed teeth include not onlyteeth with caries but also filled teeth with carious lesions or defective fillings. Missing teethinclude both missing and nonfunctional teeth. Dlil?is the total of these three categories. Thirdmolars are included in the count.

19

Table 8. Mean number of decayed , missing, and filled (DMF) teeth among adults, including edeneu-10US persons, by race, sex, and age: United States, 1960-62

Sex and age

18-24

25-34

35-44

45-54

55-64

65-74

75-79

18-24

25-34

35-44

45-54

55-64

65-74

75-79

Both sexes

Total, 18-79 years---------------------------------------------------

J&

Total, 18-79 years---------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

Women

Total, 18-79 years---------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

years----------------------------------------------------------------

Allcacea

20.4-

19.6

13.6

16.2

18.1

20.8

24.5

26.7

28.6

21.1

14.4

18.4

20.1

22.1

25.7

27.7

29.6

bite

21.2-

20.6

14.4

17.3

19.3

21.6

25.4

26.9

28.8

21.9

15.1

19.2

20.8

22.8

26.2

27.9

29.8

Negro

14.5—

12.9

8.3

8.4

9.4

14.9

18.4

23.7

*

15.7—.

9.2

13.6

15.1

15.8

21.2

25.2

*

NOTES : Where categories are no’t listed for a specific race-sex group, the sample size wastoo small for reliable estimates to be presented.

Filled teeth include only teeth with satisfactory fillings. Decayed teeth include not onlyteeth with caries but also filled teeth with carious lesions or defective fillings. Missing teethinclude both missing and nonfunctional teeth. DMF is the total of these three categories. Thirdmolars are included in the count.

Table 9. Actual and expectedmean number of decayedtulous men and women,

, missing, and filled (DMF) teeth among den-by race and family income: United States, 1960-62

Race and family income

All races

Under $2,000----------------------------------$2,000-$3,999---------------------------------$4,000-$6,999---------------------------------$7,000-$9,999---------------------------------$10,000 and over------------------------------Unknown---------------------------------------

White

Under $2,000----------------------------------$2,000-$3,999---------------------------------$4,000-$6,999---------------------------------$7,000-$9,999---------------------------------$10,000 and over------------------------------Unknown-----------------------’---------------

Under $2,000----------------------------------$2,000-$3,999---------------------------------$4,000-$6,999---------------------------------

Actual

15.315.217.218.619.017.2

18.016.617.818.819.218.3

12.210.210.2

Men

Ex-pected

18.117.316:816.917.417.3

19.318.117.817.918.418.2

12.211.210.3

Differ-ence

-2.8-2.10.4;.;

-0:1

-1.3-1.50.0

%:0.1

-:::-0.1

Actua1

15.917.218.919.720.318.8

18.018.019.319.920.319.5

12.712.813.5

Ex-pected

18.818.418.118.418.818.9

19.619.218.919.219.619.6

13.412.812.8

Differ-ence

-2.9-;.;

1:3

-:::

-1.6-1.2

::?

-::;

-0.70.00.7

NOTES: Where categoriesare not listed for a specific race-sex group, the sampletoo small for reliable estimates to be presented.

size was

Filled teeth include only teeth with satisfactoryfillings. Decayedteeth with caries but also filled teeth with carious lesions or defectiveinclude both missing and nonfunctionalteeth. DMF is the total of thesemolars are included in the count.

teeth include not onlyfillings.Missing teeththree categories.Third

21

iace and family income: United Statea, 1960~62Table 10. Actual and expected mean number of decayed teeth among dentuloua men and women, by


All racea


White


Under $2,000----------------------------------$2,000-$3,999---------------------------------$4,000-$6,999---------------------------------

Actua 1

2:1.6

::;1.6

1.82.01.6

M1.6

1.8

t::

Men

Ex-pected

1.41.5

::2

;:2

1.31.51.51.51.41.4

1.81.81.9

Differ-ence

:::

-:::-0.50.l

0.5

;:?-0.4-0.50.2

-%:-0.1

ActuaL

Women

Ex-pected

:::1.41.41.31.3

1.21.21.3

::$1.2

2.22.42.3

Differ-ence

;::-0.2-0.4-0.60.2

0.1

-::!-0.2-0.50.l

-M-0.3

Noms : Where categories are not listed for a specific race-sex group, the sample s)i.zewastoo small for reliable estimates to be presented.

Filled teeth include only teeth with satisfactory fillings. Decayed teeth include not onlyteeth with caries but also filled teeth with carious lesions or defective fillings. Missing teethinclude both missing and nonfunctional teeth. DMF is the total of these three categories. Thirdmolars are included in the count.

22

Table 11. Actual and expected mean number of missinz teeth amcnuz dentulousmen and women, byrace and family income: Unite~ States, 1966-62


All races


White


Negro

Under $2,000---------------d------------------$2,000-$3,999---------------------------------$4,000-$6,999---------------------------------

Actual

11.39.2

%;

1%;

13.19.79.08.8

1!::

9.97.47.0

Men

Ex-pected

11.09.48.5

:::9.6

12.09.78.8

!:;9.8

9.48.27.2

Differ-ence

-::20.3

-::;1.1

::;0.2

-::;1.2

-::;-0.2

Actual

10.710.29.59.3

1;:$

11.710.49.69.3

1:::

;::8.8

Ex-pected

1$;

9:19.310.010.4

10.9

;:!

1::210.4

9.68.68.7

Differ-ence

0.3

%:0.0-1.8-0.2

R

-:::-1.8-0.3

-:.;

0:1


Filled teeth include only teeth with satisfactoryfillings. Decayed teeth include not onlyteeth with caries but also filled teeth ~th carious lesions Or defectivefillings.Missing teethinclude both missing and nonfunctionalteeth. DMF is the total of these three categories. Thirdmolars are included in the count.

23

Table 12. Actual and expected mean number of filled teeth among dentulous men and women, by raceand family income: United States, 1960-62


All races


Nhite

Under $2,000----------------------------------$2,000-$3,999---------------------------------$4,000-$6,999---------------------------------$7,000-$9,999---------------------------------$10,000 and over------------------------------Unkno~m---------------------------------------

Negro

Under $2,000----------------------------------$2,000-$3,999---------------------------------$4,000-$6,999---------------------------------

Actual

2.34.26.88.810.14.9

3.1

?:;9.010.35.6

0.61.31.5

Men

Ex-pected

5.8

:::6.96.56.3

7.37.0

1,11.21.3

Differ-ence

-3.5-2.20.0

:::-1.4

-3.0-2.0-0.31.3

-:::

-0.50.10.2

Actual

3.55.0

::;11.37.I.

5.05,7t:9.611.58.2

0.8

;:;

Ex-pected

7.1

;::7.7

;:;

7.68.1P.58.5

;:2

1.61.81.8

Differ-ence

-3.6-2.40.5

;:;-0.1

-2.6?.4(.).01.1

;:;

-0.80.00.9


Filled teeth include only teeth with satisfactory fillings. Decayed teeth include not onlyteeth with caries but also filled teeth with carious lesions or defective fillings. Missing teethinclude both missing and nonfunctional teeth. DMl is the total of these three categories, Thirdmolars are included in the count.

Table 13. Actual and expectedmean number of decayed,missing, and filled (IMP) teeth among den-tulousmen and women, by race and education:United States, 1960-62

.

Race and education

All races

Under 5 years---------------------------------5-8 years--------------------------------------9-12 years------------------------------------13 years and over-----------------------------

Under 5

White

veals---------------------------------.5-8 years -------------------------------------9-12 years------------------------------------13 years and over-----------------------------

Negro

Under 5 years---------------------------------5-8 years -------------------------------------9-12 years------------------------------------

ictual

14.516.417.418.3

16.617.718.218.4

13.911.59.3

Men

Ex-pected

18.8::.$

16:8

20.019.417:517.7

13.811.69.7

Differ-ente

-4.3-2.00.91.5

-3.4-1.7

::;

-% :-0.4

ictual

15.017.918.719.3

16.019.119.319.6

13.212.812.8

Ex-pected

19.819.518.018.3

20.520.418.819.1

14.713.712.1

differ-ence

-4.8-1.60.71.0

-4.5-1.30.50.5

-1.5-0.90.7

NOTES: Uhere categoriesare not listed for a specific race-sex group, the sample size was toosmall for reliable estimates to be presented.

Filled teeth include only teeth with satisfactoryfillings. Decayed teeth include not onlyteethwith caries but also filled teeth with carious lesions or defective fillings.Missing teethincludeboth missing and nonfunctionalteeth. IMF is the total of these three categories. Thirdmolars are included in the count.

25

Table 14. Actual and exvected mean number of decaved teeth among dentulous men and women. bvrace and education: Unite~ States, 1960-~2

Race and education

All races

Under 5 years---------------------------------5-8 years-------------------------------------9-12 years------------------------------------13 years and over-----------------------------

White

Under 5 years---------------------------------5-8 years-------------------------------------9-12 years------------------------------------13 years and over------------------ -----------

Negro

Under 5 years---------------------------------5-8 years-------------------------------------9-12 years------------------------------------

Actua1

1.41.71.70.8

1.41.6

;:Z3

1.81.81.8

Men

Ex-pected

1.31.31.61.5

1.21.21.51.5

;:;2.0

Differ-ente

0.10.4

-H

0.20.4

-::?

0.2

-% ;

Women

&ctual

2.01.71.40.7

H

M

2.12.22.4

Ex-pected

1.11.21.41.4

:::1.31.2

1.72.02.6

Differ-ence


Filled teeth include only teeth with satisfactory fillings. Decayed teeth include not onlyteeth with caries but also filled.teeth with carious lesions or defective fillings. Missing teethinclude both mLssing and nonfunctional teeth. DMF is the total of these three categories. Thirdmolars are included in the count.

26

Table 15. Actual and expected mean number of missing teeth among dentulous men and women, byrace and education: United States, 1960-62

.

Race and education

All races


WA

Under 5 years---------------------------------5-8 years--------------------------- ----------9-12 years--------------------------- ---------13 years and over-----------------------------

K!Z2?

Under 5 years--------------------------------”-5-8 years--------------------------- ----------9-12 years--------------------------- --------.

Actual

12.411.7

::;

14.412.59.16.4

11.98.95.7

Men

l%x-pected

12.011.18.18.4

13.011.68.48.6

11.1

::;

Differ-ence Actual

11.612.29.27.4

12.312.89.37.4

10.59.98.3

Women

Ex-pected

11.711.1

::;

11.811.4

::;

11.610.17.7

Differ-ence

-0.11:1

-::;

0.51.4

-;::

-1.1-:.;

.


Filled teeth include only teeth with satisfactory fillings. Decayed teeth include not onlyteeth with caries but also filled teeth with carious lesions or defective fillings. Missing teethinclude both missing and nonfunctional teeth. ~ is the total of these three categories. Thirdmolars are included in the count.

27

Table 16. Actual and expected mean number of filled teeth among dentulous men and women, by raceand education: United States, 1960-62

Race and education

All races


White


Negro

Under 5 years---------------------------------5-8 years-------------------------------------9-12 years------------------------------------

Actual

0.7

2:;11.0

0.9

H11.2

0.20.9L.7

Men

l%x-pected

5.55.96.86.8

::;7.67.6

1.01.11.3

Differ-ence

-4.8-2.80.14.2

-4.9-3.0-;.:

.

-0.8-:.:

.

Actual

i::

1!:;

::;

1?:;

0.70.72.1

Women

Ex-pected

7.0;.:

7:5

7.77.98.58.3

1.41.61.9

Differ-ence

-——

-5.6-3.20.53.7

-5.8-3.2;.;.

-0.7-0.90.2


Filled teeth include only teeth with satisfactory fillings. ‘Decayed teeth include not onlyteeth with caries but also filled teeth with carious lesions or defective fillings. Missing teethinclude both missing and nonfunctional teeth. DMF is the total of these three categories. Thirdmolars are included in the count.

28

Table 17. Mean number of decayed, missing, and filled (DMF) teeth among dentulous white andNegro men and women, by family income and education: United States, 1960-62

.

Men

Family income and education

Family income

Under $2,000------------------------------------------------------$2,OOO-$3,999-----------------------------------------------------$4,OOO-$6,999-----------------------------------------------------

Education

Under 5 years”---------...-,----------------------------------------5-8 years---------------------------------------------------------9-12 years--------------------------- --------------------------- -.

Whitel

16.316.717.6

16.016.717.7

Negro

12.210.210.2

13.911.59.3

Women

Whitel

16.917.219.3

15.918.218.6

Negro

12.712.813.5

13.212.812.8

lValue for white population adjusted to be comparable with value for Negro population computa-tion explained in Appendix III.


29

Table 18. Actual and expected mean number of decayed, missing, and filled (DMF) teeth among den-tulous men and women, by race and region: United States, 1960-62

Race and region

All races

Northeast-------------------------------------South-----------------------------------------West------------------------------------------

White


-Y!3322


Actual

19.514.7’16.7

20.015.917.6

13.410.810.6

Men

Ex-pected

17.217.117.2

18.118.018.2

11.011.610.9

Differ-ence

-;::-0.5

-;:?-0.6

-:::-0.3

Actual

20.515.618.9

20.916.619.4

15.1EL.713.7

Ex-pected

18.618.218.6

19.319.019.4

13.313.012.6

Differ-ence

-R0.3

-;::0.0

-:::1.1

NOTE : Filled teeth include only teeth with satisfactory fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious lesions or defective fillings. Missingteeth include both missing and nonfunctional teeth. DMF is the total of these three categories.Third molars are inaluded in the count.

30

Table 19. Actual and expectedmean number of decayed,missing, and filled (DMF) teeth among den-tulous men and women, by race and place description: United States, 1960-62

Race and place description

All races

SMSA-in central city--------------------------

SMSA-outside central city---------------------

Urban-not .96A---------------------------------

Rural farm----------------------------------

Rural nonfarm -------------------------------

White

SMSA-in central city---------------- ----------


Urban-not SMSA--------------------------------

Rural farm------------------------- ---------

Rural nonfarm-------------------------------

J!!2&2?

SMSA-in central city--------------------------


Urban-not SMSA--------------------------------

Rural farm----------------------------------

Rural nonfarm-------------------------------

Actual

17.2

18.7

16.5

14.2

15.8

18.5

18.9

17.0

15.8

17.3

11.4

12.7

11.6

9.5

11.1

Men

Ex-pected

17.3

17.i

17.0

17.6

17.1

18.2

18.1

17.9

18.7

18.0

11.1

10.2

12.3

10.8

11.8

Differ-ence

-0.1

1.6

-0.5

-3.4

-1.3

0.3

0.8

-0.9

-2.9

-0.7

0.3

2.5

-0.7

-1.3

-0.7

Actual

18.6

20.3

16.3

15.6

17.3

19.4

20.5

17.3

17.1

18.0

14.3

13.1

9.9

10.9

13.0

Women

Ex-pecte(

18.6

18.[

18.i

18.:

18.:

19.4

19.3

19.0

19.5

19.0

13.1

13.1

12.8

12.1

13.5

Differ-ence

0.0

1.7

-1.9

-2.9

-1.0

0.0

1.2

-L.7

-2.4

-1.0

1.2

0.0

-2.9

-1.2

-0.5

NOTE : Filled teeth include only teeth with satisfactory fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious lesions or defective fillings.Missingteeth include both missing and nonfunctionalteeth. DMF is the total of these three categories.Third molars are included in the count.

Table 20. Actual and expected mean number of decayed, missing, and filled (DMF) teeth among den-tulous men and women, by race and population-size group: United States, 1960-62

Race and population-size group

Giant

Other

Other

Other

Rural

Giant

Other

Other

Other

Rural

Giant

Other

Other

Other

Rural

All races

metropolitan areas----------------------

very large metropolitan areas-----------

standard metropolitan statistical areas-

urban areas-----------------------------

areas-----------------------------------

White




urban areas-----------------------------

areas-----------------------------------

&52Q




urban areas-----------------------------

areas-----------------------------------

Actual

U3.7

18.1

17.2

16.0

15.5

19.6

18.8

17.7

16.6

L7.4

12.2

10.6

11.6

L2.7

9.5

Men

Ex-pected

17.4

17.2

17.1

17.0

17.2

18.3

18.1

18.0

17.9

18.1

10.5

10.5

11.9

li.9

11.4

Differ-ence

1.3

0.9

0.1

-1.0

-1.7

1.3

0.7

-0.3

-1.3

-0.7

1.7

0.1

-0.3

0.8

-1.9

Actual

20.1

19.8

18.5

16.1

17.1

20.8

20.3

18.9

17.3

18.0

15.0

14.2

13.2

9.7

13.1

Women

Ex-pected

18.7

18.5

18.5

18.1

18.4

19.5

19.2

19.2

18.9

19.2

13.1

13.0

13.1

12.7

13.1

Differ-ence

1.4

1.3

0.0

-2.0

-1.3

1.3

1.1

-0.3

-1.6

-1.2

1.9

1.2

0.1

-3.0

0.0

NOTE : Filled teeth include only teeth with satisfactory fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious lesions or defective fillings,,Missingteeth include both missing and nonfunctional teeth. DMF is the total of these three categories.Third molars are included k the count.

32

Table 21. Actual and expected mean number of decayed, missing, and filled (DMF) teeth among den-tulous men and women, by race and urban-rural residence: United States, 1960-62

Race and urban-rural residence

All races

Urban---------------------------------------

Rural---------------------------------------

White

Urban---------------------------------------

Rural---------------------------------------

Urban---------------------------------------

Rural---------------------------- -----------

Actual

17.6

16.3

18.4

17.4

11.6

10.8

Men

Ex-pected

17.2

17.2

18.1

18.1

11.2

11.4

Differ-ence

0.4

-0.9

0.3

-0.7

0.4

-0.6

Actual

18.7

18.0

19.4

18.8

13.3

12.4

Women

Ex-pected

18.5

18.4

19.3

19.2

13.0

13.0

Differ-ence

0.2

-0.4

0.1

-0.4

0.3

-0.6


33

Table 22. Mean number of decayed, missing, and filled (DNF) teeth among dentulous white andNegro men and women 18-34 jears of age: United”States, 1966-62

Race and sex

White

Men------------------------------------------------------------

Women----------------------------------------------------------

Men------------------------------------------------------------

Women ----------------------------------------------------------

TotalDMFteeth

15.7

16.8

8.3

11.0

Decayed

1.9

1.6

2.2

3.1

Missing

5.7

6.4

4.7

6.0

Filled

-—

8.0

8.8

1.3

1.9”

NOTE: Filled teeth include only teeth with satisfactory fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious lesions or defective fillings. ‘Missingteeth include. both missing and nonfunctional teeth. DMF is the total of these three categories.Third molars are included ~n the count.

34

Table 23. lteannumber of decayed, missing, and filled teeth among dentulous white men and women18-34 years of age, by family income: United States, 1960-62

Family income

Under $2,000------------------

$2,000-$3,999-----------------

$4,000-$6,999-----------------

$7,000-$9,999-----------------

$10,000 and over--------------

Unknown-----------------------

TotalDMFteeth

13.1

14.4

16.0

16.9

16.5

15.0

lecayed

3.1

2.4

2.0

1.3

1.4

2.0

Missing

5.0

5.4

6.1

6.1

4.6

6.0

I Women

TotalFilled DLXF Decayed

teeth

5.0 13.1 1.6

6.6 14.7 2.8

8.0 17.6 1.4

9.5 18.9 1.2

10.5 18.5 0.7

7.0 15.1 1.8

Missing Filled

5.8 5.7

6.4 5.4

6.9 9.4

6.5 11.2

6.1 11.7

5.7 7.6

NOTE : Filled teeth include only teeth with satisfactory fillings. Decayed teeth include notonly teeth with caries but also filled teeth with carious lesions or defective fillings. Missingteeth include both missinz and nonfunctional teeth. DMF is the total of these three categories.Third nmlars are included ~n the count.

35

Table 24. Mean number of decayed, missing, and filled teeth among dentuloua white men and women18-34 years of age, by education: United Statea, 1960-62

Education

Under 5 years-----------------

5-8 years---------------------

9-12 years--------------------

13 years and over-------------

Unknown-----------------------

----------------------Tots1DMFteeth

7.6

13.6

16.2

16.0

12.1

Men

)ecayed

3.4

2.5

2.4

0.9

0.5

Missing

3.6

7.3

6.2

4.4

4.4

Filled

0.6

3.8

7.6

10.7

7.2

:ota 1DMF:eeth

10.1

14.2

1.7.3

17.3

16.5

Women

)ecayed

2.9

2.7

1.7

0.8

0.8

Missing

5.2

8,3

6.7

4.9

6.2

Filled

2.0

3.3

9.0

11.5

9.6

NOTES: Where categories are not listed for a specific race-sex.group, the sample size was toosmall for reliable e;timates to be presented.

Filled teeth include only teeth with satisfactory fillings. Decayed teeth include not onlyteeth with caries but alao filled teeth with carious lesions or defective fillings. Missing teethinclude both missing and nonfunctional teeth. w is the total of these three categories. Thirdmolars are included in the count.

36

THE DENTAL

The dental examination of the Health ExaminationSurvey is designed to gather comparable information onthe dental health status of the population. As a result,the examination procedure has been standardized so thatnot only the same examiner but different examinerscan obtain their findings on a uniform basis. The dentalexamination consists of determining the condition ofthe teeth- i.e., whether a tooth is decayed, missing, orfilled-and of assessing malocclusion, oral hygiene, andperiodontal disease through the use of “i??dexes.r’ Thepresence or absence of fluoride and nonfluoride opaci-ties of the maxillary anterior teeth is also recorded.The dental examination is performed by the dentistmember of the health survey team. A portable chairand light are used, and the mouth mirror and explorerexamination of the teeth and gums usually requiresabout 10 minutes.

To determine the condition of individual teeth on auniform basis and to restrict the examining dentist’sjudgment to as narrow a range as possible, objectivecriteria have been set up and are followed throughoutthe examination procedure. The various criteria rep-resent a line drawn at a high common denominator ofspecific conditions; a line or denominator which, inmost instances, is visible evidence of a condition which,when seen by most dentists, would bring agreement thatthe condition does indeed exist. A tooth, for example,is considered “nonfunctional—loss of supprting struc-ture” when its total mobility labiolingually or bucco-lingually exceeds three millimeters. Similarly, whendetermining whether a tooth is carious, the examinerfirst looks for evidence of decay-undermined enamel inpits and fissures, opacity of marginal ridges, and de-calcified areas on smooth surfaces. Once observed,suspected lesions are considered carious only when abreak in the enamel can be demonstrated with anexplorer.

“Should see own dentist at an early date” ischecked when the individual presents a condition whichsuggests that an examination by his own dentist isdesirable in order to arrive at a clinical diagnosis ofthe condition and to determine whether or not treat-ment is neede~ otherwise, “at next regular appoint-ment” is checked. Each person examined is informedby the examining dentist that the survey examinationmust not be considered a substitute for an examinationby his own dentist.

EXAMINATION

EXPLANATION OF FIND!NGS

Edentulous Arches

An edentulous arch is identifieci b} a checL. in tlheappropriate box. The lm!i which indicates the presenceor absence of a denture for that arch is then checked.A denture is scored present only when in the examinee’smouth at the time of the examination and not defective.

An arch in which the crown of an erupting tooth canbe seen or in which roots only are present is also con-sidered edentulous if a full denture is being used. Thepresence of erupting teeth and roots under a full den-ture is noted in the remarks.

The box which designates a defective denture shouldbe checked only when there is visible evidence that thedenture is causing extensive destruction of the primarystress-bearing areas of the ridge or palate. Tissue inthese areas may be acutely inflamed; bone resorptionmay have occurred; hypertrophiecl tissue may be pres-ent. The denture is also defective if it is in the posses-sion of the examinee at the time of the exam itnt icm butnot in the mouth.

Status of Tooth Spaces

The status of each tooth space in an zrch shoukl berecorded when that arch has at least one tooth or roorpresent and a full denture is tmt being used. The sym-bol indicating the condition of the space IS written inthe upper section of each respective tooth space IMX.

Primary teeth are numbered and scorsd the sameas permanent teeth but with a circle around the symbol.When the succedaneous tooth is also present, the symbolsfor the primary tooth are placed above the upper xrchor below the lower, circled, and a line is drawn fromthe circle to the tooth’s pz$iticm in the permanent arch.

The examiner should dete.-mine the condition oftooth spaces in accordance with the criteria listed be-low. Circumstances which in some instances may pre-vent a reasonable application of the criteria should beexplained by the examiner under “Remarks. ”

(N) h’onnal. —Unfilled teeth free from carious Ie-sions are scored (N).

(D) Cavious.—Unfilled teeth with carious lesionsare scored (D). Each tooth is first examined

37

(M)

(MSC)

(F)

(FD)

(XD)

visually for evidence of decay—decalcifiedareas, opacity of marginal ridges, and un-dermined enamel in pits and fissures. Onceobserved, suspected smooth surface lesions areconsidered carious only when a break in theenamel can be demonstrated with an explorer.Missing. —When a missing tooth is not replacedby a prosthesis the tooth space normally oc-cupied by that tooth is scored (M).Missing-space closed. —A tooth space is scored(MSC) when less than 3 mm. separates theteeth bounding it mesiodistally.Filled (including crown). —Teeth which have

satisfactory fillings or crowns and present nocarious lesions are scored (F).Filled defective (OV tooth both filled andcarious) .— Filled (or crowned) teeth with newor recurrent carious lesions are scored (FD).Filled teeth which are not carious are scoredsimilarly when the restoration is1. Loose2. Temporary3. Fractured and the base or pulpal wall of the

cavity preparation exposed.Nonfunctional-cam”ous. —When caries has pen-etrated the pulp chamber of a tooth, that tooth

is scored (XD). Teeth are scored so when thereis1. Visible evidence of periapical abscess or

exposure.2. Visible evidence of extensive undermining of

all enamel w,alls.

NOTE: All roots are scored (XD) and X is placed in the

(XP)

(Xo)

(R)

(RD)

lower section of the tooth space box.

Nonfunctional-loss of supporting structure. —When the mobility of a tooth exceeds 3 mm. asmeasured at the incisal or occlusal third of thecrown or when the tooth is repressible in itssocket, the tooth is scored (XP).Nonfunctional— other. —An (XO) score is enteredfor all teeth with occlusal surfaces contactingthe opposing alveolar ridge when the :remainingteeth are in occlusion.Replaced on fixed bridge OY Yernovable partialdenture. —When a missing tooth is replaced ona fixed bridge or removable partial denture, thespace normally occupied by the missing tooth isscored (R).Replaced defective. —Missing teeth replaced on adefective fixed bridge or a defective removablepartial denture are scored (RD).

Table I. Mean number of tooth status findings by specif fed categories among dentulous aclults, byrace: United States, 1960-62

Tooth status

Total—decayed, missing, and filled teeth ---------------------------

No-l --------------------------------------------------------------------

Carious -------------------------------------------------------------------

Filled defective (or tooth both filled and carious) -----------------------

Nonfunctional-carious ----------------------------------------------------

Nonfunctional—loss of supporting structure -------------------------------

Nonfunctional-other ------------------------------------------------------

Filled (including crom)--------------------------------------------------

Hiss ing --------- . --- - ------ ---- - ----------- - ---- ----- ------ ---- -- - --- --- - -

Missing—s pace closed -----------------------------------------------------

Replaced on fixed bridge or removable partial denture ---------------------

Replaced defective --------------------------------------------------------

Allraces

17.9

14.1

1.1

0.4

O.G

0.1

0.0

7.0

5.6

0.4

2.8

0.1

White

18.7

13.3

0.9

0.4

0.3

0.:1

0.0

7.8

5.5

0.4

3.1

0.1

Negro

12.2

19.8

1.9

0.1

1.1

0.1

0.0

1.5

6.2

0.3

1.0

0.0

NOTE: DMF teeth include all teeth except normal ones.

38

Fixed brid~es are defective Removable partial dentures are defective1.

2.

3.

When o;e of the abutmenr teeth is nonfunc-tional due either to caries or loss of sup-porting structure or when there is visibleevidence of periapical pathology.When the connection of the pontic with itsabutment is broken.When an abutment crown or inlay is defectivedue to one of the following reasons:A. Tooth structure exposed by abrasion of

the crown or inlay is carious.B. A carious lesion at one of the margins

of the restoration has resulted in exten-sive undermining of an enamel wall.

1. When o{e of the abutment teeth is nonftmc-tional due to caries or loss of supportingstructure or when there is visible evidenceof periapicaI pathology.

2. When there is visible evidence that the den-ture is causing extensive destruction of thestress-bearing areas of the ridge or palate.

Table I shows the mean number of teeth classifiedaccording to the above criteria among dentulous adultsin the U.S. population.

ooo—

39

APPENDIX Il.

DEMOGRAPHIC TERMS

Age —The age recorded for each person is the ageat last birthday. Age is recorded in single years.

Race—Race is recorded as “white, ” “Negro,”or“other. ” “Other” includes American Indian, Chinese,Japanese, and so forth. Mexican persons are includedwith “white”’ unless definitely known to be Indian or

of another nonwhite race.Population size —The five classes comprising this

characteristic were derived from the design of thesample, which accomplished a stratification of the pri-mary sampling units by population size in each of threebroad geographic locations. Because the survey wasstarted in 1960, the primary sampling units within eachof the five population-size classes were necessarilybased on populations and definitions of the 1950census.Tbe name of each selected primary kamplingunitwithineach population-size class and geographic locationalong with other select,ed sample data is presented inan earlier report.7

The definitions for each of the five population-sizeclasses are as follows:

Giant m.etwpolitan a~eas.—This class includes pri-mary sampling units defined in the census as stand-ard metropolitan statistical areas (SMSA ‘s) havinga population of 3,000,000 persons or more.

O(he?’ very large metropolitan ayeas. —Included inthis class are standard metropolitan statisticalareas with a population of 500,000 to 3,000,000 asdefined by the 1950 census.

Other standanl metropolitan statistical ayeas. —This class includes other SMSA ‘s.

Othev urban areas. —This includes primary sam-pling units which are highly urban in compositionbut are not defined as SMSA’s.

Rwal areas. —This includes primary sampling unitswhich are primarily rural in composition accordingto census definitions.

Region. —For the purpose of classifying the popu-lation by geographic area, the United States was dividedinto three major regions. This division was especially

made for the design of the HES sample. The regions andthe States included are as follows:

Re@”on States Included

Northeast --------- Maine, Vermont, New Hampshire,

Massachusetts, Connecticut, RhodeIsland, New York, New Jersey,Pennsylvania, Ohio, and Michigan

South ------------- Delaware, Maryland, District of

West ------------

Columbia, West Virginia, Virginia,North Carolina, South Carolina,Georgia, Florida, Kentucky,Tennessee, Alabama, Mississippi,Arkansas, Louisiana, Oklahoma,and Texas

Washington, Oregon, California,Idaho, Nevada, Montana, Utah,Arizona, Wyoming, Colorado, NewMexico, North Dakota, SouthDakota, Nebraska, Kansas, Minne-sota, Iowa, Missouri, Wisconsin,Illinois, and Indiana

Urban and rural. — For the first six primary sam-pling units where examinations were conducted, the defi-nition of urban and rural is the same as that used in the1950 census. These locations are Philadelphia, Pa.,Valdosta, Ga., Akron, Ohio, Muskegon, Mich., Chicago,111., and Butler, Mo. For the remainder of the samplingunits the 1960 census definitions are used.

The change from 1950 to 1960 definitions is ofsmall consequence in the survey since only six loca-tions were affected. The major difference is the designa-tion in 1960 of urban towns in New England and of urbantownships in New Jersey and Pennsylvania.

According to the 1960 definition, the urban popula-tion comprises all persons living in (a) places of 2,500inhabitants or more incorporated as cities, boroughs,villages, and towns (except towns in New England, NewYork, and Wisconsin); (b) the densely settled urbanfringe, whether incorporated or unincorporated, ofurbanized areas; (c) towns in New England and town-ships in New Jersey and Pennsylvania which contain noincorporated municipalities as subdivisions and haveeither 25,000 inhabitants or more or a population of

2,500-25,000 and a density of 1,500 persons or more per

40

square mile; (d) counties in States other than the NewEngland States, New Jersey, and Pennsylvania that haveno incorporated municipalities within their boundariesand have a density of 1,500 persons or more per squaremile; and (e) unincorporated places of 2,500 inhabitantsor more not included in any urban fringe. The remainingpopulation is classified as rural.

Place desc?’iption.-In this survey the urban popula-tion is classified as living “in the central city” or “out-side the central city” of an SMSA. The remaining urbanpopulation is classified as “not in SMSA.”

The definitions and titles of standard metropolitanstatistical areas are established by the U.S. Bureau ofthe Budget with the advice of the Federal Committee onStandard Metropolitan Statistical Areas.

Tim definition of an individual standard metropolitanstatistical area involves two considerations: first, acity or cities of specified population to constitute thecentral city and to identify the county in which it is lo-cated as the central county; and, second, economic andsocial relationships with contiguous counties which aremetropolitan in character so that the periphery of thespecific metropolitan area may be determined.

Persons “in the central city” of an SMSA aretherefore defined as those whose residency is in thecity appearing in the stand and metropolitan statisticalarea title. Persons residing in an SMSA but not in thecity appearing in the SMSA title are considered to beresiding “outside the central city. ”

The remaining population is allocated into rural-farm and rural-nonfarm groups. The farm populationincludes all persons living in rural territory on places

of 10 acres or more from which sales of farm productsamounted to $50 or more during the previous 12 monthsor on places of less than 10 acres from which sales offarm products amounted to $250 or more during thepreceding 12 months. Other persons living in ruralterritory are classified as nonfarm. Persons are alsoclassified as nonfarm if their household paid rent forthe house but their rent did not include any land usedfor farming.

Education. —Each person is classified by educationin terms of the highest grade of school completed. Onlygrades completed in regular schools, where persons aregiven a formaI education, are included. A “regular”school is one which advances a person toward an ele-mentary or high school diploma or a college, university,or professional school degree. Thus, education in voca-tional, trade, or business schools outside the regularschool system is not counted in determining the highestgrade of school completed.

Income of family or unrelated individuals.. -Eachmember of a family is classified according to the totalincome of the family of which he is a member. Withinthe household all persons related to each other byblood, marriage, or adoption constitute a family. Un-reIated individuals are classified according to theirown income.

The income recorded is the total of all incomereceived by members of the family in the 12-monthperiod preceding the week of interview. Income fromall sources is included, e.g., wages, salaries,. rentsfrom properties, pensions, help from relatives, and soforth.,

41

APPENDIX Ill.

STATISTICAL NOTES

The Survey Design

The first cycle of the Health Examination Surveyemployed a highly stratified multistage probabilitydesign in which a sample of the civilian, noninstitutionalpopulation of the conterminous United States 18-79years of age was selected. At the first stage, a sampleof 42 primary sampling units (PSU’s) was drawn fromamong the 1,900 geographic units into which the UnitedStates was divided. Random selection was controlledwithin regional and size-of -urban-place strata intowhich the units were classified. As used here a PSUis a standard metropolitan statistical area or one tothree contiguous counties. Later stages result in therandom selection of clusters of typically about fourpersons from a neighborhood within the PSU. The totalsample included some 7,700 persons in 29 differentStates. The detailed structure of the design and theconduct of the survey have been described in previousreports .6’7

Reliability

The methodological strength of the survey derivesespecially from its use of scientific probability samplingtechniques and highly standardized and closely con-

trolled measurement processes. This does not implythat statistics from the survey are exact or withouterror. Data from the survey are imperfect for threemajor reasons: (1) results are subject to samplingerror, (2) the actual conduct of a survey never agreesperfectly with the design, and (3) the measurement proc-esses themselves are inexact even though standardizedand controlled.

The first-stage evaluation of the survey was re-ported in reference 7, which dealt principally with ananalysis of the faithfulness with which the samplingdesign was carried out. This study notes that out of the7,700 sample persons the 6,672 who were examined—aresponse rate of over 86 percent—gave evidence thatthey were a highly representative sample of the ci-vilian, noninstitutional population of the United States.Imputation of rionrespondents was accomplished by at-tributing to nonexamined persons the characteristics ofcomparable examined persons as described in reference7. The specific procedure used amounted to inflatingthe sampling weight for each examined person in orderto compensate for sample persons at that stand of thesame age~sex group who were not examined.

There were 6,672 persons who came in for examina-tion. Of these, 19 did not receive a dental examination;and 1,170 did not receive a periodontal score because

Table II. Number of persons examined and number for whom DMF scores were available, by age andsex: Health Examination Survey, 1960-62

Age

18-24

25-34

35-44

45-54

55-64

65-74

75-79

Total, 18-79 years ------------------------------

years -------------------------------------------

years -------------------------------------------

years -------------------------------------------

years -------------------------------------------

years -------------------------------------------

years -------------------------------------------

years -------------------------------------------

Number examined

Men

3,091

411

675

703

547

418

265

72

Women

3,581

534

746

784

705

443

299

70

Number with DMF teeth

Men

2,587

403

662

656

431

262

139

34

Women

2,896

524

697

702

552

267

132

22

42

Table III. Standard errors in mean score of DMF teeth in adults, by race, sex, and age: UnitedStates, 1960-62

TotalDMF

teethDecayed Nfiss ing Filled

Sex and age

!Jegro Negro WhiteWhite White White Negro Negro

Both sexes

Total, 18-79 years --------

Men

Total, 18-79 years --------

years ---------------------

years ---------------------

years ---------------------

years ---------------------

years ---------------------

years ---------------------

years ---------------------

Women

Total 18-79 years ---------

years ---------------------

years ---------------------

years ---------------------

years ---------------------

years ---------------------

years ---------------------

years ---------------------

0.30 0.31 0.05 0.14 0.23 0.26 0.21 0.16

0.07 0.20 0.26 0.54

0.59

0.58

0.73

0.74

0.96

1.53

7.42

0.54

0.23 0.25

0.46

0.54

0.33

0.53

0.49

0.19

0.17

0.19

0.66

0.33

0.34

0.41

0.45

0.18

0.34

0.43

0.38

0.36

0.51

0.58

0.50

1.44

0.33

0.44

0.41

0.38

0.52

0.53

0.52

1.91

0.45

1.05

0.92

0.85

0.99

1.51

1.90

7.59

0.50

1.01

1.11

0.94

0.97

1.79

2.94

8.46

18-24

25-34

35-44

45-54

55-64

65-74

75-79

18-24

25-34

35-44

45-54

55-64

65-74

75-79

0.17

0.08

0.10

0.13

0.15

0.10

0.22

0.06

0.14

0.12

0.11

0.10

0.09

0.09

0.23

0.64

0.25

0.25

0.41

0.42

0.47

0.50

0.16

0.21

0.21

0.24

0.26

0.40

0.28

1.29

0.24

0.31

0.39

0.42

0.73

1.10

1.85

0.24

0.25

0.35

0.26

0.44

0.58

0.76

1.92

0.40

0.34

0.31

0.56

0.42

0.75

1.09

0.25

0.56

0.82

0.95

0.79

2.31

3.02

7.66

0.40

0.37

0.33

0.31

0.48

0.54

1,51

they were edentulous. Thus a total of 5,483 persons role of the sampling error has been the determinationreceiveda DMF score. Tledistributionofthesepersons ofhow imprecise thesurveyresults maybebecause theybyageand sexis given intablell. come from a sample rather than from the measure-

ment of all elements in the universe.Sampling and Measurement Error The estimation of sampling errors fora studyof

the type of the Health Examination Survey is difficultln the present rep-t, reference has been madeto for at least three reasons: (l) measurement error and

efforts to minimize bias andvariability of themeasure- “pure” sampling error are confounded inthedata—itment techniques. is not easy to finda procedure which will either com-

The probability design of the survey makes possible pletely include both or treat one or the other separately,the calculation of sampling errors. Traditionally the (2) the survey design and estimation procedure are

43

Table IV. Standard errors in mean scores of DMF teeth in adults by selected characteristics, sex,and race: United States, 1960-62

.

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26—

Total DMF teeth

Characteristic Men Women

White Negro White Negro

Family income

Under $2,000--------------------------------------- 0.89 1.29 0.68 0.67

$2,OOO-$3,999-------------------------------------- 0.53 1.21 0.54 0.90

$4,OOO-$6,999-------------------------------------- 0.34 1.25 0.32 1.20

$7,ooo-$9,999-------------------------------------- 0.56 2.10 0.37 1.12

$10,000 or more ------------------------------------ 0.53 3.74 0.64 3.81

Unknom -------------------------------------------- 0.77 1.17 0.69 1.19

Education

None or under 5 years------------------------------ 1.68 1.49 1.11 1.51

5-8 years------------------------------------------ 0.43 0.83 0.50 0.72

9-12 years----------------------------------------- 0.34 0.75 0.31 0.86

13 years or more----------------------------------- 0.44 2.10 0.46 1.57

Unknow -------------------------------------------- 1.67 1.58 1,74 3.86

Region

Northeast------------------------------------------ 0.30 1.15 0.26 1.03

South---------------------------------------------- 0.86 0.59 0.89 0.60

West ----------------------------------------------- 0.42 0.90 0.45 1.04

Population-size group

Giant metropolitan areas--------------------------- 0.42 1.05 0.28 1.20

Other very large metropolitan areas---------------- 0.84 1.79 0.60 0.62

Other standard metropolitan statistical areaa------ 0.86 1.82 0.80 1.91

Other urban areas---------------------------------- 1.39 1.06 1.34 1.21

Rural areas---------------------------------------- 1.14 0.76 0.97 1.08

Place description

SMSA-in central city------------------------------- 0.51 0.43 0.50 0.51

SMSA-outside central city-------------------------- 0.40 1.51 0.28 0.82

Urban, not SMSA------------------------------------ 1.12 2.13 0.77 1.87

Rural, farm-y-------------------------------------- 1.59 1.65 1.00 1.58

Rural, nonfarm ------------------------------------- 0.89 0.52 0.57 0.68

Urban-rural residence

Urban---------------------------------------------- 0.45 0.60 0.46 0.62

Rural---------------------------------------------- 0.44 0.63 0.46 0.69

44

Table IV. Standard errors in mean scores of D~ teeth in adultsby selected characteristics,sex,.-----and race: United States, 1960-bZ—Con.

=

1

2

3

4

5

6

7

8

9

LO

L1

L2

L3

L4

L5

1.6

L7

L8

L9

~o

~1

L2

~3

~4

~5

L6—

45

Decayed Missing Filled

Men Women Men Women Men

Jhite Negro White Negro Jhite Negro Jhite Negro Jhite !Jegro

0.15

0.32

0.82

1.03

0.64

0.49

0.25

0.17

0.27

1.06

0.44

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

White Negro

0.38

0.21

0.38

0.52

2.59

0.38

0.39

0.39

0.39

0.54

0.63

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0;81

0.52

0.30

0.43

0.42

0.70

1.72

0.56

0.31

0.30

1.73

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.98

0.86

0.85

1.98

3.72

1.09

1.57

0.77

0.63

3.27

1.65

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.66

0.45

0.28

0.42

0.41

0.70

1.06

0.52

0.23

0.44

1.95

*

.*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.62

0.95

0.93

1.27

2.77

1.13

1.48

0.83

0.82

1.33

3.61

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.52

0.35

0.26

0.42

0.42

0.48

0.32

0.33

0.21

0.37

1.06

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.21

0.48

0.53

1.07

0.52

0.63

0.16

0.22

0.38

1.57

0.24

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.54

0.32

0.26

0.33

0.51

0.38

0.59

0.34

0.23

0.50

0.85

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.18

0.19

0.08

0.08

0.11

0.32

0.32

o.i2

0.10

0.08

0.21

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.15

0.14

0.05

0.10

0.09

0.15

0.22

0.12

0.07

0.09

0.28

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

0.31

0.29

0.31

0.46

2.33

0.55

0.57

0.28

0.18

0.53

0.81

*

*

*

*

*

*

*

*

*

*

*

*

*

*

*

complex and, accordingly, require computationally in-volved techniques for the calculation of variances, and(3) from the survey are coming thousands of statistics,many for subclasses of the population for which thereare a small number of sample cases. Estimates ofsampling error are obtained from the sample data andare themselves subject to sampling error when thenumber of cases in a cell is small, or even occasionally,when the number of cases is substantial.

Estimates of approximate sampling variability forselected statistics used in this report are presented intables III and IV. These estimates have been preparedby a replication technique which yields overall vari-ability through observation of variability among randomsubsamples of the total sample. The method reflectsboth “pure” sampling variance and a part of the meas-urement variance.

In accordance with usual practice, the intervalestimate for any statistic may be considered the rangewithin one standard error of the tabulated statistic,with 68 percent confidence; or the range within twostandard errors of the tabulated statistic, with 95 per-cent. confidence.

Expected Values

In tables 8-15 and 17-20 the actual mean DMF teethand their components for the various demographic vari-ables are compared with the expected. The computationof expected means was done as follows:

Suppose that in an area (say, the Northeast) theHealth Examination Survey estimates that thereare Ni persons of a particular race in the J“th agegroup (i=1,2 . . . 7, sum of N, = N).

Suppose the Health Examination Survey estimatesthat the mean DMF level for persons of this partic-

ular race for the United States in the ith agegroup is X,. Then the expected mean DMF score forthis specific race for the area is

Comparison of an actual value for, say, a regionwith the expected value for that region is undertakenon the assumption that a meaningful statement can bemade which holds in some average way for all personsin the region. This may or may not be true. The speci-fied region may have higher values for younger personsand lower values for older persons than are found in

other regions.In that case an average comparison will obliterate

one or both of these differentials. In arriving at thegeneral conclusions expressed in the text, an effort wasmade to consider all the specific data, including datanot included in this report; but it must be recognizedthat balancing such evidence is a qualitative rather thana quantitative exercise. The standard error of the dif-

ference between an actual and an expected value may beapproximated by the standard error of the actual table(table HI).

In addition to tables 8-15 and 17-20, expected valuesare computed for figure 5. The computation of Dk, themean deviation adjusted for education of the mean DMFteeth for sex-income group k, was done as follows:

Let Xij~ be the estimated mean DMF teeth forpersons in sex-income group k who are in the i ‘hage group and the jth education group. Let n, j ~be the estimated number of peopIe in that group.

Let

Let

The

njk= ; I’I,,k

Z njk dlkDk= i

~ ‘jk

dik =~ Z2i,k(xljk-Xij

njk

where

Adiusted Values

In table 17 the mean DMF teeth for white personsin a specified income or educational group were adjustedto the distribution of the Negroes in the same group. Theadjusted mean number for white persons in the kt h sex-income or educational group was computed as follows:

Let X, kbe thewestimated mean DMF teeth for whitepersons in the sex-income group or sex-education

group k who are in the age group i.Let m,~ be the number of Negro persons in thatgroup.Then Xk= Xiknlk where ~ n,k= YIk

‘k

Tests af Significance

Tests of significance for the demographic variableswere performed in two ways. The first was to divide

the difference between the actual and expected valuesby the standard error of the actual value. For example,for white men with annual incomes of $2,000-$3,999 theactual number of teeth given a DMF score was 1.5 lessthan expected, and the standard error was 0.53. Sincethe difference was approximately three times its stand-ard error, it may be deemed statistically significant.

The second method was to examine the age-specificdifferences (not published) between the prevalence forthe specified and the prevalence for all persons. Thus,for women from rural areas, the mean DMF score forall seven age groups was less than the overall means

46

Table V. Average number of missing second andthird molars per adult,by single years of agefrom 18-34 years: Health Examination Survey,1960-62

Age

18-24 years ---------

years ------------------years ------------------years ------------------years ------------------years ------------------years------------------years ------------------

25-34 years ---------

years ------------------years ------------------years ------------------years ------------------years ------------------years ------------------years ------------------years ------------------years ------------------years ------------------

Average number ofmissing molars

Second

0.4

0.20.20.40.4:.;

0:6

Third

2.1

2.92.3

1.92.1

R2.12.32.32.52.62.5

for these age groups . The probability ofsuchan occur-rence is 0.01, and the difference hetween theactual andexpected values (which is really a weighted average ofthe age-specific differences)isl .22 times its standarderror which is not statistically significant.

Small Numbers

In some tables magnitudes are shown for cells forwhich sample size is so small that the sampling errormay be several times as great as the statistic itself.Obviously in such instances the statistic has no mean-ing in itself except to indicate that the true quantity issmall. Such numbers, if shown, have been includedtoconvey an irnpressio no ftheoverallstory of the table.

Overestimation of DMF Counts

In order to estimate the amount by which the DMFcounts might have been overstated because of includingunerupted third molars, a special study was made of theyoungest age groups. .l’%eaverage numbers of missingsecond and third molars per adult aged 18-34 yearsbysingle years of age are shown intable V and figure I,These data indicate that for ages 18-24 the numberofmissing third molars cannot be more than 2.1 and isalmost surely less than 1.7. ‘Ihus, it is probable thatthe missing component of the DMF counts for 18-24year olds is exaggerated at least by 0.4and not morethan 2.1, as aresultofincludinguneruptedthird molars.

3

2

I II

o I I I I I I I I I I I I I 1 Iis 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34

AGE

Figure 1. Average number of missing second and third molars per adult, by single years of age from ages 18-W years.

—000 47

* U. S. GOVERNMENT PFfR4TING OFFICE :1973 543-979/13

OUTLINE OF REPORT SERIES FOR VITAL AND HEALTH STATISTICS

Series 1.

SeTies 2.

Sevies 3.

Seyies 4.

SeVies 10.

Series 11.

Series 12.

Series 13.

Sevies 20.

Series 21.

Series 22.

Programs and collection procedures.— Reports which describe the general programs of the National

Center for Health Statistics and its offices and divisions, data collection methods used, definitions,and other material necessary for understanding the data.

Data evaluation and methods Yeseavch. —Studies of new statistical methodology including: experi-mental tests of new survey methods, studies of vital statistics collection methods, new analyticaltechniques, objective evacuations of reliability of coIlected data, contributions to statistical theory.

Analytical studies. — Reports presenting analytical or interpretive studies based on vital and healthstatistics, carrying the analysis further than the expository types of reports in the other series.

Documents and committee reports. — Final reports of major committees concerned with vital andhealth statistics, and documents such as recommended model vital registration laws and revised birthand death certificates.

Data j%om the Health interview Survey. —Statistics on illness, accidental injuries, disability, use ofhospital, medical, dental, and other services, and other health-related topics, based on data collectedin a continuing national household interview survey.

Data fvom the Health Examination Survey. —Data from direct examination, testing, and measure-ment of national samples of the population provide the basis for two types of reports: (1) estimatesof the medically defined prevalence of specific diseases in the United States and the distributions ofthe population with respect to physical, physiological, and psychological characteristics; and (2)

analysis of relationships among the various measurements without reference to an explicit finiteuniverse of persons.

Data j?om the Institutional Population Surveys.— Statistics relating to the health characteristics ofpersons in institutions, and on medical, nursing, and” personal care received, based on nationalsamples of establishments providing these services and samples of the residents or patients.

Data from the Hospital DischaYge Survey. —Statistics relating to discharged patients in short-stayhospitals, based on a sample of patient records in a national sample of hospitals.

Data on mortaMy.-Various statistics on mortality other than as included in annual or monthlyreports —special analyses by cause of death, age, and other demographic variables, also geographicand time series analyses.

Data on nutality, marriage, and divoyce. —Various statistics on natality, marriage, and divorce otherthan as included in annual or monthly reports— special analyses by demographic variables, alsogeographic and time series analyses, studies of fertility.

Data porn the National NataLity and MoYtality Swveys. —Statistics on characteristics of births anddeaths not available from the vital records, based on sample surveys stemming from these records,including such topics as mortality by socioeconomic class, medical experience in the last year oflife, characteristics of pregnancy, etc.

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