thomas rakosi cefalometrie

8/10/2019 Thomas Rakosi Cefalometrie

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An

Atlas

and

Manual

of

Cddmetric

Radiogr

Thomas

akosi,

M.f).,

D.D.S.

Professor

f Orthodontics,

Chairman

f

the

Orthodontic

epartment,

University

of

Freiburg.

Translated

y R. E. K.

Meuss

WolfeMedicalPublications td


3/224

O

ri

ginally

published

y

Carl

llanser-Ve-rlag'

Munich

as

Atlas

Und

Rnteitung

Zur

Pral(tscnen

Fernrontgenanalyseff

omas

Rakosl'

@

1979

Carl

Hanser

Verlag

This

book

s

one

of

the

itles

n

the

series

f

W;if;

Medical

Atlases,

a

series

which

brings

ion"ttt.t otobablyheworld'sargest

ystematic

;1

li$;i

;;lG;iil

of

dia

gnostic-colour

hoto raphs'

Fot

u

full

list

of

Atlases

n

the

series,

lus

i"tttt**i"g

titles

and

details

f

our

surgical'

a*t"t

and

eterinary

Atlases

please

rite

o

Wolfe

Medical

Publi-cations

td,

Wolfe

House'

3

ConwaY

treet,

ondon

W1P

6HE'

General

Editor,

Wolfe

Medical

Atlases:

G.

Barry

Carruthers,

D(Lond)

ISBN

O72A

U67

3

This

edition

@

1982

Wolte

Medrcal

ruor

Printed

in

Great

Britain

bY

Eb*n"""t

Baylis

&

Son

Ltd,

Worcester'

tograPhicand

'

iexi"uf,

may

not

be

reproduced

n

3nyl?rm'

by

prt

ffi

apttt-,

phototransparency'

icr-o- lm'

iniirohctre,

r

any

othei

means,

or

may

t

b.e.

included

in

any

computer

retriev-al.system'

ithout

1982

Wolfe

Medical

Publications

Ltd'


4/224

Foreword

The

use of cephalometric

adiography

n orthodontics

serves o

confirm diagnosis,

and

also makes t

possible

o include

the morphology

of

the

visceralcranium when

considering

possible

reatment

procedures.

n

the

course

of treatment, oentgeno-

graphic analysis an

give

valuable ndications,by

providing

additionaldata when

treatment

is first initiated,

a

monitoring function as treatment progresses,

nd

suggesting

ossible

modifications.On conclusion f treatment t will

often be the

most

mportant

method

or determining

tabilityas

well

as he

period

of retention.

Cephalometric

eleradiographywill not, of course, eplace

any of the established

methods

of investigation.

Radiographic

iagnosisather han

analysis-i.e.making

important.therapeutic ecisionswhbly on the basisof radiographs-would ndeed

be

poor

diagnosis.

o emphasize

his

point, the echnique

will

always

e

referred o

as'cephalometric

adiography' nd not as'diagnosticadiography'.

The

method

presented

n this book

is a

practical

one, .e. designed

or

use

n daily

practice.

A

great

number

of analytical

nd

nvestigatory rocedures

re

specifically

designed

o

assist

cientiflc esearch.

The

present

method

also

nvolves

scientific

researches ut, if

at all, theseare mentioned

only

in

passing.

A

method designed

or

practical

use

must be based

on

meaningful

measurements.

All

kinds

of measurements

may be

made on

a radiograph,

but

we

are concerned

only

with

parameters

hat

provide

he data

needed or

decision-making.

nalysis

s

basedon elements hosenwith greatcare,based n theexperience f manyyears.

Its

information

value has been tested

repeatedly, ncluding

the

retrospective

analysis

of

completed

cases.For a

period of two

years,

he work

of our under-

graduate,graduate

and

postgraduate

tudents

has

beenassessed

nd checked or

accuracyby J. Jonas.

Her conclusions

ave

assisted

s n the

choiceof landmarks.

As exact

definition

of

the different landmarks

s

of supreme

mportance, he

chapter

on

o'X-ray

Anatomy" included n

the

present

olumehas

been aken rom

her work.

In

the

planning

of this

book, didactic

aspects

ereconsidered

swell

as he medical

and

scientific

content.

Its

precursor

entitled

Leitfaden

filr

die Femrontgenkurse

(manual

or the

coursesn cephalometric

adiography)waspublished

n 1973.

On

the insistenceof those who have attended our courses, he material from

innumerable

courses

s now

presented n concise

orm.

The

introductory

chapters discuss

he

general

principles,

X-ray

anatomy, land-

marks,

lines

and angles.This is followed

by chapterson the

significance f various

skeletal,

dental

and

soft

tissueassessments.

wo

further

chaptersdeal with the

interpretation

of results and of

growth.

Finally,

practical

examples

are used to

demonstrate

treatment planning

on

the basis

of radiological

criteria. Countless

examples

ould

have been

given

o illustrate

his chapter; he

commonest orm

of

malocclusion,

the class

It

anomaly,

has been used

to demonstrate

he

issues

involved.


5/224

The

conclusions

rawn

n

that

chapter

show

hat

the

usefulness

f

cephalometnc

radiography

is

not^llmiffi

a;

on"ruil

*ut*""t

planning'

Every

stage

of

treatment

and

innumerable

t".t

rri.uf

details

"t;;;;

pLnn

O

J.t

ttt.

basis

of

radiographic

findings.

Even

*;;;-;;;;tsiOereO"simi[

p'tottOutes'

such

as

determining

he

angle

of

traction

f;;;;"dg"ar,

plannirrg

tb

construciion

bite

or

trimming

the

acrylic

of

an

activ-ator,

cinnot'u"".^ii&tin"ry-p"tr"t

ed

without

radiological

analysis.

t-,-

^

The

aim

of

the

book

is

to

integrate

cephalometric

adiography

as

far

as

possible

with

investigatio;lnJtr*t*.it

ph;;i;in-.tt.

n"ro

of

o--rttrodontics,

o

facititate

decision-making

n

daily

practice,

."JJ""uG

the

best

form

of

treatment

to

be

determined

or?ach

individual

case'

Freiburg-im-B

eisgau,

GermanY

August

1978

Th.

Rakosi

15

t6

16

T6

l7

t'l

18

Contents

Cephalometry

nd

Radiographic

nalysis

1

The

Introduction

of

Cephalometry

o

Orthodontics

2

Classification

of

AnalYses

.

i.t

rrlieittoOorogicalClassification

;.t

NormativeClassification

;.i Ciurrin.ution ttotoing

to

the

Area

of

AnalYsis

3

Producing

he

Cephalometric

adiograph

4

Diagnostic

;;;fi""t

of

the

Radiograph

4.1

Landmarks

4.2

Lines

and

Planes

4.4

The

Range

f

AnalYsis

4.4

InterpretationofMeasurements

X-ray

Anatomy

of

the

Visceral

Cranium

L

Norma

ateralis

;

ii;;t

outlines

in

the

RadiograPh

3 Paranasal inuses

1

The

Roof

of

the

orbit

5

The

SPhenoid

one

6

The

Maxillary

Sinus

-

i

fn"

PterygoPalatine

ossa

8

The

Middle

Cranial

sase

Landmarks

1

Reference

Points

i.f

Ftop"tti"t

of

Refeqence

oints

1'.i

bednition

of

Reference

Points

2

Reference

Lines

i Angular andLinear Measurements

3.1

Angles

3.2

LinearMeasurements

Page

n

8

8

13

20

20

22

24

26

28

30

a^

34

34

J)

4T

42

42

M


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Significance

f

Angular

andLinear

Measurements

or

D

ento-Skeletal

nalysis

1

Analysis

f the Facial

Skeleton

1.1

Saddle

ngle

I.2

Articular

Angle

1.3

Gonial

Angle

1.4 Sumof thePosterior neles

1.5

Linear

Measurements

Cianial

ase

nd

Facial

eight)

2

Analysis

f Maxillary

ndMandibular

ases

2.1

SNA

Angle

2.2

SNB

Angle

2.3

ANB

Angle

2.4

Comparison

f

SNA,SNBand

ANB

2.5

SN-Pog

2.6

SN-Pr nd

SN-Id

2.7

Horizontal

ines

2.8

Basal

Plane

nglePal-MP

2.9 Angleof Inclination

2.IO

SN-MP

2.t1,

N-S-Gn

Y

Axis)

2.I2

Anterior

andPosterior

acial eight

D

ento-Alveolar

nalysis

3.1

Angulation

f

Upper ncisors

3.2

Angulation

f Lower

ncisors

3.3

Assessment

f Incisor

osition

3.4

Inter-incisalAnsle

4

Linear

Measureirents

n Skeletal

tructures

4.I

Extent

f

Anterior

Cranial ase,

ella

Entrance Nasion

4.2

Extent

of Posterior

ranial ase.

ella

Articulare

4.3

Dimensions

fMandibular

ndMaxillaryBase

4.4

Position

f

Maxilla n

thePosterior

ection

Soft

Tissue

nalysis

1

Profile

Analysis

1.1

Reference

oints

sed n

Profile nalysis

1,.2

Assessment

f Total

Profile

2

Lip

Analysis

2.1,

Ivletric

ip

Measurements

2.2 ReferencelanesorLip Profile ssessment

3

Analysis

fTongue

osifion

yCephalometric

46

46

47

47

53

54

54

55

55

) /

58

60

60

60

61

62

62

65

65

3.1

3.2

4

Radiography

Tongue

Parameters

Average

Findings

Functional

nalysis

ased n Cephalometr ic

Radiography

66

67

68

68

71,

7T

11

II

71

76

78

79

80

90

90

92

96

98

98

r01

Interpretation

f Measurements

I

Facial

Profiles

nd

SkeletalAnalyses

1.1

OrthognathicSkeletalRelationship

I.2

RetrognathicSkeletalRelationship

1.3 PrognathicSkeletalRelationship

1.4

Age

and

Treatment-Related

hanges

n

Cases

of Prognathic

elationship

1.5

Corelative

Comparison

f

Sagittal

Malocclusions

104

105

109

113

123

r27


7/224

2

Assessment

f Vertical

Relationships

n

the

Facial

Skeleton

2.1

Growth-Related

otation

of the Mandible

2.2 Determination

f the Centreof Rotation

2.3

The Significance

f Mandibular

Rotation

2.4

Rotation

of the Maxilla

2.5

Rotation

asa Factor

n

Treatment

Planning

2.6

Horizontal

Rotation

of

the Mandible

and

Deep

Bite

2.7

Vertical

Rotationof the

Mandibleand Open

Bite

3

Classification

f Facial

Types

Cephalometric

adiography

nd

Growth

1

HowMuchFurtherGrowthMaybeExpected?

2

Time

Table for

Growth

3 Localisation f GrowthRates

4

Direction

of Growth

5 Prediction

f Growth

5.1

Methods

of

PredictingGrowth

5.2

Sources

f Error in GrowthPrediction

6 Post

Treatment

Growth

Changes

6.1 Fine

Adjustment

of

Occlusion

fter

Treatment

158

7

Holdaway

Growth Prediction

161

7.I

The Twelve

Stages f

the HoldawayAnalysis 161

CephalometricRadiographyn TreatmentPlanning

i

The Role

of

Cephalometric

adiographyn

130

130

133

133

135

r37

137

140

t47

1.1

r.2

1.3

r .4

1.5

2

2.1

2.2

149

I49

149

1s1

151

151

153

157

164

165

165

169

169

169

1,69

170

Treatment

or

Class

I' Patients

Localisation

f the Malocclusion

Functional

ssessmentf Class

I

Occlusion

Growth

Direction

Growth Potential

Aetiological

Assessment

Detailed

Treatment

Plan

Elimination

of Dysfunction

The Usefulnessf Cephalometric

Radiography

ith

FunctionalOrthodontic

Treatment

2.3

Distal

Movement

n theMaxilla

2.4

Combined

herapy

2.5

DiscrepancyCalculation

3

Late

Treatment

3.1

Planning

he

Anchorage

4

Correction

of

Class

I, Malocclusions

ith

Vertical

Growth Direction

TheRankingOrderof Cephalometric

Radiography

n

Orthodontic

iagnosis

Appendix

185

r93

201

208

209

214

zt5

272

223


8/224

C.phalometry

and

Teleradiography

1 TheIntroduction f Cephalometry

o

Orthodontics

The assessment

f

craniofacial

dimensions

s

not

a new

skill in

orthodontics.

The

earliest

method

usedwas

o

assessacial

proportions

rom

an artisticpoint

of view,

with

beauty

and harmony

as he

guidingprinciples.

Tastes

hange,

however,

and

beautywas

udged

by

different

standards

n

antiquity

han,

or

example,

uring

he

Renaissance.

Dtirer

analysed he human face,

determined

he ideil

proportions

and divided

he

ace

nto quadrants,

ndhiswork

still has

a

bearing

n

orihodontics.

Mqly centuries ater, his method was applied to the analysis f cephalometric

radiographs

by

de

Costerand

Moorees.Cephalometry

scientific

meaiurement

of

the

dimensions

f the head)was

he first method

o

prove

of value n

orthodontics.

It

was

used

o assess

raniofacial

rowth

and determine

reatment

esponses.

ore

accurate

methods

were

based

on oriented

mpressions

f the

faceand

dentures,

n

example

being

hat

of van Loon

(cubus

craniophorus).

he method

s

demanding

but very

useful

and was ntroduced

under the name

of

'gnathostatics'

n

t922.

A

further

method

for

the

analysis f craniofacial

dimensions

hat

developed

on the

basis

of cephalometry

s cephalometric

adiography.

The

first

X-ray pictures

of the

skull

in the

standard

ateral

view were

taken

by

Pacini and Carreru (L922). In subsequentyears, the following authors also

produced

his

type

of radiograph or the evaluation

of craniofacial

measurements:

MacGo-wen

1923),

Simpson 1923),

comte

(1927),

Riesner

lgz9),

and

others.

Nolg

of them gave

an

accurate

escription f the

methods

sed

o take

he pictures

and for

their

evaluation,

so hat

one

can

only speak

of individual

studies.

t wasnot

until L93I

that

Hofrath

and Broadbent simultaneously

and independently

developed

standardised

methods or the

production

of cephalometric

adiographs,

usingspecial

holders

known

ascephalostats,

o

permit

assessment

f

growth

and

of

treatment

esponse.

Cephalometric

adiography

was

ntroduced

nto

orthodontics

uring

he

1930s,

ut

the method

really

only

gained

wider

acceptanceor

practical

pplication

during he

last twentyyears.Over theyears,a whole rangeof analysesasbeendeveloped y

a number

of authors.

The aims

of assessmentended

o vary,

ranging

rom

studies

on facial growth,

the location

of

malformations,

etiological

tudies

o the

assess-

ment

of

treatment

response,

s a complement o status

analysis

n

orthodontics,

etc.

An analysis

will

only

supply

he

answers

o

a

particular

set of

questions,

nd

these

answers

will

depend

on correctapplicationof

the method

and nterpretation

of results.

Over a hundred

different analyses ave

been developed.

hey may

be classffied

rom

a number

of viewpoints, n systems

evised

y different

authors.

For

clinical

application,

he methodsdesigned

o assist

iagnosis

re

of

particular

interest.

The many

different diagnostic nalyses

ay be

differentiated

n

a

number

of

ways,

according

o

the method

of

deteimination,

he standards sed, or the

particular

basisof

analysis.


9/224

2

Classfficationf Analyses

2.I Methodological

Classification

The basicunits ofanalysis re angles

nd

distances

n millimetres

lines).

Measure-

ments (in degreesor millimetres)may be treatedas absoluteor relative, or they

may be related

to each

other

to

express

roportional

correlations.

2.1,.1

Angular

Analyses

The

basic

units are angledegrees.

2.1,J. Dimensional

analysisconsidersh.e arious

angles

n isolation,comparing

them

with average igures.

Down's

analysis

s

of

this

type

(1948;

Fig. la,

b).

2.L.I.2 Proportional analysiss basedon comparisonof the variousangles o

establish

significant

elations

between

he

separate

parts

of the facial skeleton.

Koski's

(1953)

analysis

belongs o this

group, and this

was developed urther

by

Koski and

Virolainon

(1965).

The results

obtained

with this

analysis

give

the

relations between the basic

reference

planes

OP-N

and OP-Pog in

per

cent

(Fig. 2).

2.L.1,.3

Analyses

o

determine

osition

Angular

measurements

ay also

be used

to determine

he

position

of

parts

of the

facialskeleton.

The SNA andSNB angles,

for example,

give

the

relations

between

he maxillary

and mandibular

bases nd

the cranial base.

Angular measurements n their own arenot normallysufficientor cephalometry

and linear

measurements

ill

be

needed n addition.

Angular analyses ave

certain deficiencies:

The

lines

are

drawn

in relation

to a

primary reference

lane,

on

the

premise

hat

this remainsconstant. f

this

plane

showsdeviations

rom the mean, he analysis

s

not reliable. Measurements

re

often

related o

particularnorms

or

mean

values.

These

norms are however

subject to a

number of factors, such

as age,

sex,

hereditary and ethnic

predisposition,

tc. They

are basedon

averages, nd n

the

individual case t is the

deviation

rom the

mean hat

is

characteristic.


10/224

1a

-\--rrz--ti

1b

\

I

,{r

}\

l__

I

I

FH

T

\=_--

Fig.

1.

Downs' dimensional

angular

analysis

(1948)'

skeletal

analysis;

b)

Downs'dento-alveolar

nalysis.

\


11/224

2

'-ft--t-

\pNs

V

Fig.

2.

Proportional

nalysis

of

Koski

and

Virolainen

1956).

his

compares he

different ngles,

o determine ignificant

elationships

betweendifferentpartsof the facialskeleton.

2.L.2

Linear

Analyses

For linear

analysis, he

facial skeleton

s analysedby determining

certain inea

dimensions.

2.I.2.t

Orthogonal analyses. reference

plane

s established, ith the variou

reference points projected

onto

it

perpendicularly,

after

which

the distanc

between he

projections

aremeasured.Orthogonalanalysismay

be

partial

or

total

Total

orthogonal analysismay

be

geometrical

or

arithmetical.

The de Coste

method

is a total

orthogonal

geometricalanalysis

Fig.

3).

For the

arithmetical

method, the reference

points

are

projected

onto

a horizont

and a verticalreferenceplaneandthe distances etween hepointson theseplane

determined Fig.

4a,

b).

Partial

orthogonal

analysisnvolvesorthogonalassessment

f

only

part

of the

facia

skull. Willy

(1947)

or

instance

sed

he Frankfurthorizontalplane

as he referenc


12/224

r-1---

|

A--f

- (

---// I

I

L_

t i

Fig. 3.

de

Coster's total

orthogonal

geometrical

Mal-

occlusion s

demonstrated y deformation

f the

quadrants.

Orthogonal analyses re

llustrative

and suitable

or teaching ut not for diagnostic

purposes.

A further development

f orthogonal

methods

arearqhialanalyses,

nd

these are a useful diagnostic

aid.

The most widely known method

s

the

Sassouni

nalysis

1958),

with the reference

points

not

projectedperpendicularly, ut

by

drawingarcswith the aid of compasses

(Fie.

).

2.1,.2.2 Dimensional, inear analyses

re

basedon

evaluation

of

certain

inear

measurements, ither direct

or

in

projection.

The direcl method

gives certain

linear

measurements

e.g.

the length of

the

mandibular

base)

as the distance

between

wo

reference

points.

The results

are

given

in

absolute

erms,

so

that

age also

has to be taken into account

or their

mterpretatron.

Projected

inear dimensional

analysis

determines

he distances etween

certain

reference

points

that

have

been

projectedonto

a reference

ine.

2.I.2.3 Proportional linear analyses re basedon relative rather than absolute

values.

The different

measurements

re

compared

o eachother,

without reference

to norms.

I

\

\

t\

i

--l-

I

I

r

/,,

I

_l___\

I

Ll


13/224

4a

4b

\^

F 0.

4.

,

coben's

otal

orthogonal

rithmeticat

nalysi.

""""i"

skeletal

relationships

parallel

a)

and vertical b)

to

the Frankfurt

horizontal.

\^

{


14/224

5

100

66

I

Pn n

-_:r_

__ _

Fig.

5. sassouni

rchial

analysis.

andmarks

re

related

ot

vertically,

ut

by

arcs

drawn

rom

a

centreC.

2.2

Normative

Classification

Analyses

ay

also

e

classified

ccordingo

the

concepts

nwhich

ormal

alues

have

been

ased.

2.2.L Mononormativenalyse

Averages

erve

as he

norms

or

these: hey

may

be arithmetical

r

geometrical.

2.2.1.1

The

arithmetical

orms

are averageigures

ased

n

angular,

inear

or

proportional

measurements.

13


15/224

1g.9. .

Average

racing

f

geometrical

orms

or

children

ged

10

(Bolton).

2.2.L.2

Geometrical

orms

are

average

racings

n a transparent

heet.

Assess-

ment consistsn comparinghesewith the casi under

anaiysis.

hese

methods

merelyprovide

apid

orientation

Fig.

6).

2.2.1'.3

The

disadvantage

f mononormative

nalysesis

hatindividualparameters

are considered

n

isolation.

Nor

do they

necessarily

epresent

'normil'average,

as deviations

n the

ndividual

dimensions

f

the

awJ

and ace

may

compensate

each

other

so

that

occlusion

s

normal,

just

as

'normal'

measurements

ay

cumulatively

91d

o

one

end

of the

range

f normal ariation,

he

sum otal

being

malocclusion.

Mononormative

nalyses

re

suitable

nly

for group

studies,

nd

not

for

diagnostic

urposes.

2.2.2

Multinormative

nalyses

For

hese,

whole

eries

f norms

re

used,with

age

nd

sex aken

nto

account

(Tables

and2) .

2.2.3

Correlative

nalyses

These

are

used

o assess

ndividual

variations

of facial

structure

o

establish

heir

mutual

relationships.

Correlative

analyses

re the

most

suitable

or

diagnostic

pu{poses, ndare usedassuchby mosiauthors.

14


16/224

q)

q)

*c

0i -

t

'J ,

ol

(u

cn

-u

mQ?Q

I X{ \

mtr

fF

m

8/,,0

f

q1

q

1

2

3 4

5

6 7

8

I t0

11

17

13

1415

1617

18

Table

1. Multinormative

ean alues

or SNAangle. ge

and

sexanarysis.

mi4,9 mo m81,0

f76,6

fp

f91,4

1 2 3

4 5

6 7 I

I 10

11

1?

131{

15

16 17

18

Table

.

Multinormative

ean

alues

or

sNB

angle.

ge

and

sexanalysis..

2.3

Classification

ccording o the

Area

of Analysis

The

various

analyses

ay nvolve imited

areas

r

the

whole

of the acial

keleton.

2.3.1"Dentoskeletalnalyses

These

analyze he

teeth and

skeletal

structures.

They may

be made rom

norma

lateralis,

norma

rontalis,

or three-dimensionally.

more ecent

developments

three-dimensional

tereometric

analysis,but this is not

yet

fully

developed or

clinical

use.

2.3.2

Soft

Tissue

nalyses

These

may nvolve

he whole

profile

n norma ateralis,

r certain tructures

nly.

We usually

do a

partial ateral

soft issue nalysis,or

example

o analyse

he ips n

a cephalometric

adio$aph.

o

0)

q.)

o/

o-

t

o1

c)

un

-U

15


17/224

2.3.3

Functional

nalYses

cephalometric

adiographs

ay

also

be

used

o

assess

unctional

elations

uch

as

;#;;l*."i"

i",.".oiclusal

ipu.r

relationship

n

norma

ateralis

and

norma

frontalis.

3

Producing

heCephalometricadiograph

Cephalometric

adjographs

re

produced

at

a

considerable

istance

rom

tube

target

o Subject

1i-Z

ti"it";i,

;

that

the

visceral

kull

s

correctly

eproduced'

without

enlargement

i

distoriion.

The

principal

imo,f

he

diagnostic

nalysis

s

o

localise

malocclusion

ithin

the

conteni

of

the

acial

bone

structures'

valuation

"f

tfrr

i.Jiograph

is based

n

standardised

ephalometric

andmarks'

The

landmarks

are

used

o

determine

ines

and

planes

which

hen

enable

us

to

make

inear

and

angular

assessment

f

the

radiograph'

4 Diagnostic

ssessment

f

the

Radiograph

Standards,of

eneral

alidity

or

diagnostic

ssessment

o

notexist'

f

an

analysis

does

not

reveal

he

nature

of

the

anomaly

nder

nvestigation

his.need

ot

n.r.riutify

be

due-io

nuO.quu.ies

n

the

radiogfuqh,

ut

may

arise

ecause

method

f

assessmrnt

tut

been

sed

hat

was

otteiigned

or

hat

particular

rea

of

investigation.

"

tfi"ituf

practice,

valuation

f

cJphalometric

adiographs

s

based

n

he

principles

iven

elow'

4.1

Landmarks

Distinction

s made

between

entoskeletal

nd

soft

issue

oints,

and

hese

may

be

unilateral

(meOianf

o.

Ufite'ul'

pependilg-.on-,thtirorigin'

points

may

be

anatomical,

nthropological,

r

radiological

Ftg'

1,1'

(1) In

the

median

plane,

unilateral

ointsare

ocated

n

the

region

of

the

cranial

b^.,

for

instance

n

the

midface

and

n

the

profile'

(2)

Points

ocated

on

either

side

and

above

he

median

plane.result

rom

super-

i,isill*

"ftwo

lateralpoints.Themost mportantof theie ie n theregionof the

mandible.

We

prefer

unilateral

situated

n.the.median

r

sagittal

lane)

o

bilateral

oints'

as

,.pJfp"rition

of

t*o'pointr

*ittt

Uitut.ral

ocation

may

nvolve

oss

of

accuracy'

As

far

as

possible,

he

points

chosen

re

generally

nown

points

capable

f

being

easily

defined

n

a

radiograPh.

we

have

nvestigated

he

degree

of

personal

error

in

the

location

of

landmarks'

and

found

(lonurj

it

ut

anatomicat

nO

also

dental

points

are

more

reliable

han

constructed

oints.

r


18/224

lig.z.

Median

nd

bilateral

eferenceoints

sed y

Krogman

nd

Sassouni.

4.2

Lines

and

planes

Having

ocated

he

points,.we

draw

ines

o

mark

the

reference

lanes

Fig.

g).

Linear

measurements

ay

be made

by connecting

wo

points,

angular

measure-

ments

between

hree

points.

Numerous

ines

are

sed

in

the

diffeient

inear

and

angular

analyses,

ith

.one-partrcular

ine

representing

he

reference

lane

on

which the wholeanalysiss based. wo suchplun.sare he Frankfurthorizontal

Plgn.

and

the

sella-nasion.

he

Frankfurt

orizontal

plane,

being

based

on

bilateral

points

(orbitale

and porion),

s

more

subject

to

.rior.

W?

th.r.for.

prefer

the

sella-nasion

lane

which

s

constructed

ith

the

aid

of two

median

landmarks.

4.3

The

Range

f

Analysis

Diagnostic

analysis

oes

not

adhere

o

a rigid

system.

We

do

certain

inear

and

angular

measurements

n

a routine

basis,

ut

go'beyond

hese

n

individual

ases,

depending n thenatureof theanomaly, n tf,epaiient's g., unA fremethodof

treatment

under

consideration.

istinction

s

made

betweJn

pecial

nd

supple-

mentary

measurements.

l7


19/224

I

I

I

;

t

*

i

Pnn

Me

Fig.8. The

most

widely

used

eference

ines.

Sello-nosion

one

N' Fronkfurt

4.3.1,

Control

Measurements

These

are

madewhere

he

results f routinedeterminations

eave

oom

or

doubt.

W-.

9o,

for

example,

make

a routine

analysis

f the

position

of the

upper

ncisors

relative

o the

nasal

pineand

he

SN

plane.

f the results

re not

unequivocal

n

either

case

s, or

example,

n

cases

f

ante-

or retroinclination,

e

.nake

urther

measurements

n

order

o

get

a clear

picture.

As far

as

possible,

inear

and

angular

measurements

re used

n

combination.

4.3.2

Special

easurements

Special

measurements

re taken

n individualcaseswherepointsof particular

interest

arise.

An

example

would

be the

position

of the

r;15-year

molars,

which

may

be

of considerable

mportance

rior

to

andduringheadgear

herapy Fig.

9a,

b and

c).

4.3

Interpretation

f Measurements

Individual

measurements

re considered ot

in isolation,

but relative

o each

other. An

unusually

ong

mandibular

ase, or instance,

oes

not in

itself

mean

prognathism,

but may

be found

with normal

and evenpost-normal

cclusion.

What

matters

s

the

relationship

etween

he

mandible

nd

he

whole

acial

bonestructure.Only

correlative

nalysis ill

accurately

ocalise

malocclusion

ithin

the

context

of the

facial

skeleton.

a

ot

Ir I


20/224

9b

point

R

Fig.9.

Specialmeasurements

to

determinehangesn

6th-year olar

osition.

Reference

oints

a),

diagrammatic

epresentation

of R

and

Mvertical

roiection

to

give

inearmeasurements

(b),

nd

diagrammatic

representation

f

heangle

betweenheaxisof6th-year

molars

nd

SN

c)

o assess

movement

f he eeth.

9c

19


21/224

X-ray

AnatomY

f

the

Visceral

Cranium"

1

Norma

ateralis

It is oftendifficult

o

establish

clear

elationship

etween

he

size

and

shape

f

anatomical

tructures

n

the macerated kullon the onehand'and he contours

seen

n

a

lateral

teleradiograph

n

;;.;;h.t.

The

differences

re

due

to

the

technique

sed

i...

it.

tails

t..ntiuipiol.:,i"1

.il1to

reprcsenting

hree-

dimensional

tructure

n

two

dimensions'

nterpretation

s

made

more

difficult

il;iff;;les

in

density,

r

contrast

f

the

projected

tructures'

Exact

ocation

f

the

anatomical

andmarks

sed

n

cephalometric

adiology

il l

require

dequare

;;;i;dg.

oi

the

X

t.y;;.arance

ofth.

cranial

ones

nd

heir

relationship

o

adjacent

tructures'

Numerous

eatures

re

discernible,

uch

s

ines-

he

projection

f

bony

tructures'

shadows

representing

oft

tissuesl

nJ

u,gt

'uiioiuttot

areas

indicating

pneumatisation.

.

-

--^,

Below,

series

f

radiographs

nd

utline

rawinesalt^g\t:":::f:t:- t

?:fft:l

ff

."J#"T:'it?J';liiff

liffi

il;;*o"i"t'r:d"9:1'^:':::":1ffi

1"::

i*Lliii?i;tiili..iil, &rr+:;;,'i.i.ai"graphv.

he

gures

iven

n

brackets

lateral

views

have

also

been

(19),

and

he

shadow

f

the

*From

J.

Jonas,

Mathematisch-statische

rhebung

iber

die

Griissenordnung

es

ndividuellen

ehlers

ii

iir

nanryenkephalomefrie'

reiburg

'

19'75'

iotr.tponO

o

those

n

Figs'

10

o

16'

2

BonY

Outlines

n

the

RadiograPh

InFig. l0a,b, thebonyout l inesconsistent lySeeninX-raypictureshavebeen

tracei,

Their

adiodensity

ay

of

course

ary'

Moving romaboveo belown theanterior art, here,

re

he

ollowing:

he

anterior

wall

of

tt.-t-niufsinus

(1),

rr.""^J

6on.

1z;,

he

rontal

rocessf the

maxilla

3),

he

uni.iio,

wall

of

il;

.;;il.y

sinus

+),

he

loor

of

the

nose,

he

alveolar

rocess

"fi;;;;illi-(l),and

the

anterior

spect

f

the

mandible'

In

the

middle

part

of

the

picture,

he

ollowing

tructures

ay

be

discerned:

he

roof

of

the

orbit

8),

with

he

opaque

iot

tonti"nuing

nto

he

planum

phenoidale

(12),

he

cnbriform

late

f

the

ethmoi;;;;.

(to;,

no

the

upper

nd

ower

imits

of

ihe

maxillarY

inus.

Posteriorly

he

X-ray

shows:

he

hypophyseal

ossa

n

p,rofile

13)'

ts

dorsal

imit

continuing

nto

r,.?'Utii,

f

+llii;'"';

;li.

most

audal

irt

of

he

clivus

the

basion

(laa)- theshadow-"tt,l dens xis 15)may

be

seen,

nd

mesial

o

it a

smaller'

more

or

less

riangular

utline

ept.t.titittg

he

anterior

rch f theatlas16)'

Ventrally

o

these

tructures,

he

condylar

rocess

f

he

mandible

17)

s

visible;

t

continues

orwards'inio

trr

mandibular

nlisure

nd

inally

he

coronoid

rocess

(18).

Being

very

similar

o

the

macerated

kull,

he

body

and

amus

f

the

mandible

s

easily

distinguished.

Some

of

the

soft

tissue

outlines

commonly

een

n

it*.d.

fne

soft

palate

s

outlined'

with

the

uvula

pottttl"t

wall

of

ihe

nasopharynx

20)'

20


22/224

" l

10b

Fig.10. Bonycontoursn the radiograph.a) n the radiograph,

(b)

diagrammatic.

21


23/224

Paranasal inuses

Fig.

11a,

b shows he

air-filled

spaces

n

the skull.

These

re

subject

o individual

vaiiationand

heirX-ray

appearance

lso

depends n

hedegree

f

pneumatisation:

Frontalsinus 21),sphenoidal inus 22),ethmoidal ir cells 23),maxillary inus

(24)

and

nasopharyngeal

pace

25).

The

lowest

point

of

the

frontal

sinus

s at

the height

of

the nasion, he

anterior

upper end of

the frontonasal

uture.

ts

supraorbital

ecess

28

n I2a,6)

may

have

pushed

part

he

amina

nterna

and

orbitalis

of

the

nner

ableof the rontal

bone.

The

ethmoidalair

cells

(23)

ie between

he

frontal

cellsand

the body

of

the

sphenoid

one.

Their

ower

imit

s he

oof

of

themaxillary

inus,

hecranial

imit

the cribriform

plate of

the ethmoid

bone.

The marginsof the ethmoidbone are not easilydefinedbecause f its great

variability.

The anterior

air

cells

may be

masked

by

the frontal

process f

the

maxilla.The

middlecells

with

the ethmoidal

ulla

ie behind

he zygomatic

one,.

and

the

posteriorwall of

the

sinus

s

masked

y the

shadow

f the

greaterwingof

the sphenoid.

The sphenoidal inus

22)liesimmediately

elow

hesella

urcica nd

usually

asa

numberof components.

entrally

and

caudally

t extends

eyond

he

loor of

the

middle cranial

ossa.Anteriorly,

the

planumsphenoidale

orms

ts roof.

The nasopharyngeal

pace

25)

iesbetween

he

shadow

f the soft

palateand

he

upperpait of iheposteriorwall of thepharynx,t connects ith he oralcavity.At

thd tof

,

the

space

s

imited

by

a ine

hat s a

radiological

rtefact,

projection

f

the

posterior-edge

f

the

vomer.

This

is

however

masked

y the shadow

f

the

pterygoidprocesi

which

also

overs

he

posterior

art

of

thesuperior

meatus f

the

nose,so that the

atter

s only

rarely

dentifiable


24/224

11b

Fig.

1.

Paranasal

inuses.

a)

n

he adiograph,

b)

diagrammatic.

LJ


25/224

The X-ray

appearance

f

structures

ifficult

o identify

because f

the numerous

linesseen

n the radiograph

s discussed

elow.

4 TheRoof

of

the

Orbit

In the

upper

part

of

Fig.

}a,b,

the

loor

of

theanterior

ranial

ossa

s raced.

his

is formedbiliterally

Uy

tre

oof

of

the

orbit

(8)

and

n the

median y

he

cribriform

plate

of

the ethmoiO

tO;

and

he

planum

sphenoidale

I2).

The

roof of

the orbit

(8) produces

dense

utline,

usually

double

tructure,

ue

to

its

being

bilateral.

t

rnerges

orsally

nto

the

planum

phenoidal"

\I2),

almost

straight

ine, and divides

nto

two

ess

marked

tructures

entrally.

he upper

one

goes

n a cranipventral

irection,

orming

a

dorsally

oncave

ine;

the other

one

t-ends

n a more downward

direction,

unning

nto

the shadow

f

the cribriform

plate

10).

Some

pointed

elevations

re

distinguishable

n the

egion f

theorbital

oof

these

represent

he cerebral

idges

26).

The external urface

f

the

rontal

bone

erminates

ith ananteriorly

onvex

urve

in

the rontonasal

uture

30).

Krogman

nd

Sassouni

1957)

tate

hatbecause

he

caudally

adjoining

nasal

bone

(2)

differs

n radiodensity,,it

s

not always

asy

o

determine

he

uppermost

oint

of the

rontonasal

uture.

here

s a risk

of

putting

this

point

too faf

in the

dorsal

egion.

Overlap

with the eyelids

n this area

may

produce

another

ine structure

hat

could

be confused

ith

the suture.


26/224

12b

Fig.

12.

Roof

of

orbit.

a)

n

he adiograph,b)

diagrammatic.

IJ


27/224

5

The

Sphenoid

one

Fig. 13a,

b: The

outlineof the sella urcica,

onvexo the

vertex,

tands

ut clearly

from

its surroundings

n every adiograph.

t terminates

n

the

uberculum

ellae

(34)

anteriorly

and

n the

dorsum ella

35)

posteriorly.

s it is

elliptical,

double

line is often seen n this area. According o van der

Linden (lgil),

the most

radio-opaque

ines

epresenthe median

or sagittal

lane.

The

most

caudal

ine

s

the loor

of the

sella,

and

he

mostdorsal hadow

hemedian

f the dorsum

ellae

(3s).

The

image

of

the tuberculumsellae

3a)

s

frequently

masked

by the

anterior

clinoid

processes

o hat the anterior imit to

the entrance

f

the

sella

s not

always

clearly

discernible.

t doeshowever

standout from

the

surrounding

tructurbs

because

t

shows

ontinuousransition nto

the ine representing

he loor

of the

sella, with

its

shadow denser han

those

of

the

anterior

clinoid processes

(van

der Linden,

l97I).

The esser

wing (33)

shows

s

a

ine

beneathhe uberculum

ellae

34)

which

may

show

downward

renationsndicatinghe

optic

canal. he

upper

part

originatesn

the

anterior

clinoidproces,sgl

36)

and continues

n

a ventral

direction

arallel

o

the

planum

sphenoidale

12),

inally

becoming

angential

o

the

shadow

f the

greater

wing.

As

alreadymentioned,he

outlines

f the esser

ing

of thesphenoid

are

ess

adio-opaque

han hose

of

the

adjacent lanu.m

phenoidale

nd of

the

greater

wing.

Dorsal

to

the

cribriform

plate

of

the

ethmoid

bone,

the greater

wing

of the

sphenoid

appears

n relief, its facies

erebralis

orming

a

dense

road ine

that

continuesn a ventrallyconcave rc acrosshe loorof the anteriorcranial ossa,

moving

dorsocaudally.

t

produces

a double

contour

n

this

area,

the facies

cerebralis

nterna 38)

and he acies

rbitalis

39).

The acies

emporalis40)

may

sometimes

e visible

n the region

of

the

anterior

sphenoidal

inus

22).

The

contour

f the

dorsum ellae

35),

heposterior

imit

of he

ossa

ypophysialis,

continues

orsocaudally

nto the

shadow f the

clivus

14)

which

consiits

of the

body

of the

sphenoid

nd hebasilar

art

of theoccipital

one.

Theshadow

xtends

from ts

more

caudal oint,

he

basion, ranioventrally

o

the

anteriorlowerpart

f

the

sphenoid.

cross

he

broadshape f the

clivus, he

aintly

sketched

ine

of

the

sphenooccipital

ynchondrosis

42)

uns

rom

dorsocranial

o

ventrocaudal.


28/224

_-L

22

L1

------/

,. i

z7

Fig'

13.

sphenoid

one. a)

n

he

adiograph,

b)

diagrammatic.


29/224

6 The Maxillary

Sinus

The size

of

the maxillarysinusdepends

n

the degree f

pneumatisation.

Fig.

14a,

b:

The

anterior

wall of thesinus

4)

s usually learly istinguishable

rom

the

surrounding tructures.

t extends

pwards

nd

back o form heupper

imit of

the maxillarysinus. his ine sratherdelicate nd ends o be regular. It ispartly

rnaskedby the ethmoidalair cells

(23)

and

therefore

not

completely

isibleat

times.

The shadow f the

anteriorwall of

the sinus

ontinues ownwards nd back

nto

the loor of the sinus. he caudal

art

of

a

normally evelopedinus xtends elow

the

palatineprocess

f

the maxilla

6)

which

ormsa

ong,

dense

ine unningmore

or

lesshorizontallyacrosshe

picture,

erminating

entrally n the antedornasal

spine

43).

According

o

Hunter

(1968),

uperposition

f anatomical ontours

s

common

n this

area

due o thealae artilagenes

asales,nd

t is

possible

o

put

he

anterior

nasal

pine,

he mostcaudal

andanterior

point

of

the piriform

aperture,

too

far

forward.

Beneath he latter, the external

anterior

imit of the

maxilla ormsan anteriorly

convexcurye running down to

the alveolar

borderof the central

ncisors. his

contour

s not

always

ery radio-opaque,

ndwith

poor

contrast ne uns he risk

of

localising he deepest etractionof

the curve

oo far"in the distal direction

(Krogman

nd

Sassouni,

957).

The area

s alsomasked

y the soft

issues f

thecheek. his

produces

noutward

curvingshadow

n the

regionof

the anterior

imit of the

maxillary

ase, nd

may

cause

mistakesn locating

point

A.

The dorsal imit of the

palatineprocess

6)

is

represented

y

the posteriornasal

spine. n children, his may frequentlybe maskedby the images f unerupted

molars.

Ventral

o themaxillary

inus

ies he

rontal

process f themaxilla

3).

Depending

on

contrast, hismaybemoreor ess

learly istinguishable

rom hecontourof

the

nasal one.

In the upper anterior

sectionof

the

maxillarysinus

appearshe contourof the

orbital

loor

(9);

dorsal

o this

shadow

re wo approximately

arallel

ines unning

in the cranial

direction the anterior

and

posterior imits

of

the zygomatic one

(31).

Beneath he orbital

loor

(9)

an opaque,

oughly

riangular tructure

may

be

seen.

Different opinions regiven n the iterature s o whichspecificone hisbelongs.

Bouchet

et

al.

(1955)

onsidershese tructures

o form

part

of

thezygomatic one,

whilstEtter

(1970)

sed adiological

tudies

n solated

ones o demonstrate

hat

this area epresents ainly he zygomatic

rocess f the

maxilla

44).

In

the

upper

part

of the

posteriormaxillary

inus,

he

outline

of the middle

nasal

concha

45)

may

be

noted.This

appears

sa shadow

learly ounded t heback.

f

the

inferior nasal

concha

46)

s

hypertrophied,

t

may

be locatedbeneath

he

middle concha.

The coronoid

process

f the

mandible

18) ieswithin the owerpart

of

the

sinus

outline, but its contoursare rather

ndistinct.


30/224

"|&;

,,,,,,

,

..

F',

Wsr*

$"

i : .r r . i

li

Fig.

14.

Maxillary

inus.

a)

n the

radiograph,

b)

diagrammatic.

(See

ext,

page

28.)

29


31/224

7

The

Pterygopalatine

ossa

The

contour

of the

pterygopalatine

ossa

s a

roughly

riangular

shape

nding

n a

sharp

point

caudally.

Fig.

15a,b:

Its uppel

imit

is ormed

by

the sphenomaxillary

urface

f the

greater

wiig (ai). T.hem6OiAl terygoid late 48) s ts.posterior allwhilstventrally t is

limited

by the

posterior

witt

of

the

maxillary

sinus

l),.. clgarly

visible

ine

that

continuei

caudally

nto

the

maxillary

tuberosity

(51). The contours

of

the

zygomatic

rch

31)

and

caudal

o

it

the

coronoid

rocess

f themandible

18)

cut

aliort

the

uppei

part

of

the

pterygopalatine

ossa.

The

shadowof

the

foramen

rotundum

(47)

appears

n the cranial

part.

The

caudal

extension

f

the anterior

partof

the

ossa

ntersects

ith the

contour

of

the

floor of

the

nose

and

the soft

palate.

Compared

o the

macerated

kull

the

fissure

s situated

n

the ransverse

lane,at

the same

eight

as

he

posterior asal

spine.

30


32/224

ljg,.1S,.

Pterygopalatine

ossa. a)

n

the radiograph,b)

diagram-

matically.

31


33/224

8

The

Middle

Cranial

Base

In

the

middle

region

of

the

base

of

the

skull,

nterpretation

f

contours

s

made

Oim.utt

by

the

riultiplicity

of

superposed

tructures.

he

area

s also

subject

o

considerable

ndividual.and

ge-related

ariation'

Fig. 16a,b: In the upperanteriorpart of the diagram iesthe contourof the

rpfi.noid

bone,

with

the

sella

urcicd

1t:;

continuing

ownwards

nd

back

o

the

clivus

14).

Dorsal

o

the clivus

s

the

upper

nner

margin

of

the

petrous

art of

the

emporal

bone

52).

The

region

below

this

hasa

broken

up,

cloudy

appearance

ue

o

the

air-filled

mastoid

cells.

In

the

ower

part

of

the

diagram,

he

ollowing

ontours-are

hown,

moving

rom

the

anterior

o the

posterioiparts:

he

zygomat]9_1rch(32),

he

articular.tubercle

(jtl,."o the condylu,

pro.ri,

of

the

manoibte

17)which

borders

nto

he

mage

of

the

mandibular

ossa.

Basion,

he

most

caudal

point of

the

clivus

14),

s

the

most

anterior

edge

of

the

foramen

magnum,

he

hferal

border

of

which

s he

occipital

ondyles

54).Their

it*g.

upp.u"tt

lose

o the

dens

of

the

axis

15), glmjng

a

ine hat

becomes

ole

horizontal

at

its

lower

edge

and

continues'dorsally

nto

the condylar

ossa

55).

Across

he

shadow

f

the

occipital

ondyles

ies

he

contour

f

the

mastoid

rocess

(s6).

From

about

he

age

of

L4

onwards,

he

mastoid

locess

xtends

audally

eyond

the

condyles.

For-"

ifferential

diagnosis,

ts arc

is

more

strongly

co-nv.ex

o

the

cranium han hu condyles, nd t iray alsobe ocated y themastoid ir cells.

Dorsal

o

the

ower

part of

the

clivus

14) ies

he

opening

f

the external

coustic

;;;6;

(57),

an

approximately

ircular

hape,

and

dorsocranial

o

it the

smaller

contour

of

ihe

opening

o the

nternal

acoustic

meatus.

If ear

olives

are

used

with

the

cephalostat,

heexternal

coustic

eatus

resents

s

a

completely

adio-opaque

tructure.

32


34/224

- ' . . .

I

ii".lrlr

Fig.

16. Middle

ranial

ase.

a) ln

he

adiograph,

b)diagram.

mat ical ly

see

ext ,

page

2).

aa

JJ


35/224

Landmarks

I Reference

Points

The

effective

evaJuation

of

radiographs

depends

on

accurate

definition

and

localisation

of

landmarks,

which

provide

the

basis

or

all further

work.

Distinction

is

made

between

anatomical

and

anthropological

points which

are

located

on or

within

the skeletal

structures.

Radiological

or

constructed

points

are

secondary

andmarks

marking

the

int"er-

sections

of

X-ray

shadows

r

lines.

1.1

Properties

f

Reference

oints

1.1.1

Ease

of

Location

According

to Moyers

(1973), his

depends

on

the

following

actors:

1.1.1.1

Quatity

of

the

radiograph.

The

quality

of

the

picture s often

marred

by

magnification

or

distortion

Magnification

is

due

to

divergence

of

the

X-rays.

The

smaller

the

focus-film

disianle

and

he

greater he objEct-image

istance,

he

greateris

he

magnification.

Distortion arisesfrom two-dimensional

epresentation

of

a three-dimensional

object.

All

elements

not

in the

;rnag9

pl$?

are.subject

o distortion.Accurate

."ntti.tg

and

positioning

of

the

treia

win hrgely

eliminate

t.

The

median

or

sagittaftlun.

of

the

head'must

be

parallel

and

he

central

ay

perpendicular

o

the

film.

1.1.t.2

Overlapping

anatomical

contours.

Facial

structures

verlap

a

great

deal

(see X-ray

Anaiomi,

pug. 23),

so

that

the

location

of

certain

andmarks

may

present

pioblems. S;;d

ridiological

peculiarities

eed

o be

taken

nto

account

n

the

selection

of

landmarks

1.1;1.3 Observer

experience.

bserver

experience

nd

pra-ctice

lay a

major,role

in

the

interpretatibn

of

radiographs,

with

knowledgeof anatomy and X-ray

anatomy

as a

key

factor.

1,.I.2 Constancy

f

Contours

The

structures

of

the

skull

show

dependence

n a

number

of

factors

such

as

age,

sex,

growth, race,

etc.

The

constaniy

of

contolrs

is

therefore

not

entirely

reliable

in

co-ntradistinction

o

points

ocated

close

o

the base

of

the skull,

where

variation

due

to

growth

is

minimal

(..g.

nasion

and

sella).

34


36/224

20

LU

Fig.17.

Reference

oints

used

on a routine

asis.

L.2

Definition

of Reference

oints

The points

we

use

on a routine

basis re shown

n

Fig. 17.

Our definition

of them s

as ollows:

23

a

No.

Code

Definition

N

Nasion.

The

most

anterior

point

of the

nasofrontal

suture n the

median plane.

The

skin nasion

(N')

is

located

at

the

point

of

maximum

convexity

between

nose

and torehead Fig.

18).

Setla.

We use the midpoint of

the

sella (S)

in

our

analysis,

and

also

the midpoint

of

the entrance

to the

sella (S"),

after

A.M. Schwarz. he sellapoint (S) sdefinedas hemidpointof the

hypophysial

fossa.

t is a constructed

(radiological)

point

in the

median plane.

2

35


37/224

Fig.

18.

Nasion

and

soft

issue

naslon'

Fig.

20.

Subnasale,

oint

A

and

prosthion'

t

I

T

I

I

t

t

I

I

t

I

t

I

I

I

Fig.

19.

Localisation

f

S

and

Se'

3

se

Midpoint

of

the

entrance

o

the

sella,according

o

A'M'

Schwarz

t

thesamet.o" tu ' thejugumsphenoidale' ' indepe.ndent 'of ' the

depth

ot

tfre

seffa-

This

pdint

represents

he

midp-oint:ii*:::

connecting

he

posterioiclinoid

process

nd

he

anterror

opemng

of

the

sella

urcica

Fig'

19)'

4SnSubnasale.Askinpoint ; thepointatwhichthenasalseptum

merges

-"riuuj

*iti

ttre'integument

of

the

upper

lip

(Fig.

20).

I

I

I

I

I


38/224

APMax

Point

A,

subspinare.

he

deepest

midline

point

n

the

curved

bony

outline

rom

the

base

o

the

alveorar

rocess

f

the

maxilla,

.e.

at

the

deepest

oint

between

he

anterior

nasal

pine

and

prosthion.

In

anthropology,

t

is

known

,

,uurpirr"l.

iFi;.'i,ii:-

t

The

anteriorlandmark

or

d,etermining

he

ength

f

the

maxiila.rt

is

constructed

by droppingu p"rp.niicular f?;;;;i;t e to tt.

palatal

plane.

Pr

Prosthion

Arveolar

im

of

the

maxilla;

he

owest,

most

anterior

point

on

the

arveorar

ortion

or

trr.jr"*axilla,

in

the

median

plane,

between

he

upper

entral

ncisfrs

in

g.20).

Is (orIsl)

Incisor,iy,:::t

Tip

of

the

crown

of

the

most

anterior

max'lary

central

ncisor.

Ap-l

Apicale

I.

Root

apex

of

the

most

anterior

maxilrary

entrar

incisor.

Ii (or

s

T)

Incisor

nkllts

- Tivof thecrownof themostanteriormandibularcentral

ncisor.

ApT

Apicare

7.

Root

apex

of

the

most

anterior

mandibular

entral

incisor.

ld

Infradentale.

rveolar

im

of

the

mandibre;

he

highest,

most

anterior

point

on

the

alveorar

rop.rr,

ln

tn.

median

plane,

between

he

mandibular

entral

.ii"^

tpi-g.

Zt).

B

lolnt

B,

supramentale.Mostanteriorpart

of

the

mandibularbase.

It

is

the.mos_t

osterior

point

"

th;';;;.on,ou,

of

the

man_

dibular

alveolarprocess,

n

the

media;;i;;..

h

""irrrip'"i"gy,'i,s knownassupiamentale,etweenniiul.ntule andpogonion

(Fig.21).

Pog

Plsonio.y.

y?rt anterior

poinr

of

the

bony

chin,

n

the

median

plane

Fig.

21).

A

10

11

L2

L3

I4

Fig.21.

Infradentale,

oint

B

and

pogonion.

37


39/224

Gn

1,6

Go

Fig.22.

Gonion

and

gnathion.

Me

15

Gnathion.

This

point

is

defined

in a

number

of

ways,

According

to Martin

and Saller

1956),

t

is

ocated

n the

median

plne

of

the

mandible,

where

thi

anterior

curve

in

the

outline

of

the chin

merges

nio

the

body

of

the

mandible.

Many

authors

have

ocated

gnaihiott

between

he

most

anterior

and

he

most

nferiorpointof

lhe

chin.

Graig

defines

it

with

the

aid

of

the

facial

and

the

mandibularpla-ne;

according

o

Graig,

gnathion

s the

point of

intersection

of

these

wo

planes.

Muzi

and May give it as the

i;;;rt

point of

the chin

(A.M.

Schwarz

ses

he same

definition)

and

therefore

synonymous

with

Menton

(Fig'

22)'

Our

own

definition

of

gnathion

s as

he

most

anterior

and

nferior

point of

the

bony

ctrin.

tt

is

constructed

by

intersecting

a line

dr"*n

perpendicularty

o

the

line

connecting

Me

and

Pog

with

the

bony

outline.

Gonion.

A

constructed

oint,

the

ntersection

f

the

ines

angent

to

the

posterior

margin

of

ttt"

ascending

amus

and

the

manibular

base

Fig.

22).

L7

Menton.

According

to

Krogman

and

Sassouni,

Menton

is

the

most

caudal

point

ii the

outline

of

the sy_mphysis;it

s regardedas

the

lowest

point of

the

mandible

(Fig.

23)

and

corresponds

o

the

anthropological

gnathion.

The

anterior

landmark

for

determining

he

ength

of

the

mandible.

It is defined as the perpendicular dropped from Pog to the

mandibular

plane.

38

18

APMan


40/224

T9

Articulare.

This

pointwas

ntroduced

byBjork (1947).

tprovides

radiological

orieritation, being

the point

of

intersection

of the

posterior

margin

of

the ascending amus

and the

outer margin

of

the

cranial

base

Fig.2q.

Condyli,on

Most superior

point

on the

head

of the condyle

(Fig.

a) .

Orbitale.lowermost point

of the

orbit in

the radiograph Fig.

25).

A

constructed

point

It is

obtained

by bisecting

he

Pn vertical,

between

ts

intersectionwith

the

palatal

plane

and

point

N'.

Intersection

of the ideal Frankfurt

horizontal

and the

posterior

gnargin

of the ascending amus.

20

2l

22

23

Cd

Or

Pnl2

Int.FFI/

R.asc.

Fig.23. Localisation

f menton.

Articulare

and condylion.

ig.24.

39


41/224

24

ANS

PNS

5

25

Anterior

nasal

pine.

Point

ANS

is the

tip

of

the bony

anterior

nasal

pine,

n the

median

lane

ng'

25)'

It

conesponds

o

the

anthropological

canthion'

Posterior

nasal

spine.This

s

a

constructed

adiological

oint,

the

intersection

of

Jcontinuation

of

the

anterior

wall of

the

pterygo-

palatine

ossa

and

he

loor

of

the

nose.

t

marks

he

dorsal

imit

of

\

\

\-/

\or

\r/

Fig.

25.

Orbitale,

nterior

nd

27

APOcc

PPOcc

Ba

Ptm

themaxilla Fig.25).

Landmark

for

assessing

he

length

of

the

maxillary

base,

n

the

posterior

section.

t

is

efined

ai

a

perp'endicular

ropped

rom

point S

to

a

line

extending

he

palatal

plane'

Anterior

point

for

the

occlusal

plane.

A

constructed

point,

the

midpoint

in

the

incisor

overbite

n occlusion'

Posteriorpoint

for

the occlusalplane. The most distalpoint of

contact

between

he

most

posterior

molars

n

occlusion.

We

also

use

he

following

landmarks

see

Fig'

7 and

8)'

Basion.

Lowest

point

on

the

anterior

margin

of

the

foramen

magnum

n the

median

Plane'

Pterygomaxiltary

issure.

The

contour

of

the

fissure

proje._cted

onto

itre

palataipiane.

The

anterior

w_all

epresents

he

maxillary

tuberosity

outline,

the

posterior

wall

the

anterior

curve

of

the

pterygoid

process.

This point correspondso PNS.

posterior

nasal

sPine.

S'

6

28

29

40

30


42/224

.

o\9

E

n^lt

2

c*'o

1

-vl

* \ t r

't''"

K

Fig.26.

Reference

ines

used n

our analysis.

2

Reference

ines

The points

described

above

are

used o

construct

a

considerable

umber

of

lines.

Below

is a

description

of the

lines

we most requently

use

(Fig.

26).

No.

Line

Definition

1

S-N

(Se-N)

2

S-Ar

.A

J

ar-uo

4

Me-Go

5

N-A

Sella-nasion.

nteroposterior

extent

of anterior

cranial

base

Lateral

extent

of cranial

base

Length

of ramus

(1st

measurement)

Extent

of mandibularbase Lstmeasurement)

Nasion

point

A

41


43/224

6

7

B

9

10

11

L2

L3

t4

15

t6

t7

18

L9

20

2I

22

23

24

N-B

Nasion

Point

B

N-Pr

Nasion

Prosthion

N-Id

Nasion

infradentale

N-Pog

Nasion

Pogonion

N-Go Nasion gonion ine, or analysisf the

gonialangle

Pal

Palatal

lane

ANS-PNS)

Occ

Occlusal

lane

APOcc-PPOcc)

S-Gn

Y-axis

S-Go

Posterior

acial

height

1-SN

Long

axis

of upper

ncisor

o SN

1-Pal

Long

axis

of

upper

ncisor

o

Pal

1-MP

Long

axis

of

lower

ncisor

o

mandibular

lane

ManBase

Extent

of

mandibular

ase

Go-Gn,

2ndmeasurement)

MaxBase

Extent

of

maxillary

ase

APMax-PNS)

R.asc.

Cd-Go

ength

f

ramus

2nd

measurement)

S-S'

Perpendicular

rom

pointS

(starting

rom

he

SN

ine)

o

pointS'

Pn

ine

Perpendicular

o SeN,

drawn

rom

the

soft

issue

asion

N) as

far

asPal

Modified

Frankfurt

horizontal;

parallel

to

the SeN

line

which

bisects

he Pn

line

from

N

to Pal

(Pnlz-

FH/R'asc')

Aesthetic

ine.

Tip

of

nose

soft

tissuepogonion

'H'line

EL

The

reference

lines

enable

us

to

make

angular

and

linear

measurements

nd

determine

dimensions

n the

radiograph.

The

following

angles

re

determined

n a

routine

basis.

3.1, Angles (Fig.27)

3

Angular

and

Linear

Measurements

Points

of

No.

the

angle

Definition

Mean

value

N-S-Ar

S-Ar-Go

Ar-Go-Me

Sum

Ar-Go-N

Saddle

angle

Articular

angle

Gonial

angle

Sum

of sella,

articular

and

gonial

angles

Gor,

upper

gonial

angle

L23"

X

5"

1"43"

6"

r28"

t

7"

394"

52"-55"

42


44/224

I

t

\

l+ l+ J

Fig.27.

The

21 most requently etermined

ngles.

6

7

8

9

10

LT

L2

T3

T4

15

N-Go-Me

SNA

SNB

ANB

S-N-Pr

S-N-Id

Pal-MP

Pal-Occ

MP-Occ

SN-MP

Goz,

lower

gonial angle

Anteroposteriorpositionof maxilla

Anteroposterior

position

of

mandible

Difference

between

SNA

and SNB

Anteroposterior

position

of alveolar

part

of

premaxilla

Anteroposterior

position

of alveolar

part

of

mandible

Angle between

palatal

and

mandibular

plane

Upper

occlusal

plane angle

Lower

occlusal

plane

angle

Angle

between

SN

and

mandibular

plane

70":750

81,'

79"

2"

84'

81_"

25"

L1_"

14"

32"

43


45/224

16 Pn-Pal

l7 N-S-Gn

18

1-sN

19

1-Pal

20

T-MP

2I ii angle

(L

of incl.) Angle

of

inclincation fter

A.M. Schwarz

85'

(Y-axis)

Angle

between

SN

line

and S-Gn ine,

anteriorly

66"

Angle betweenupper

ncisor axisand SN line

posteriorly

102"

Angle

betweenupper

ncisor axisand

palatal

plane,

anteriorly

70"

t

Angle between

ower

incisor axisand

mandibular

plane,

posteriorly

90"

+

Interincisalangle

between

upper

and ower

central

ncisor

axes,

posteriorly 135'

) -

ao

J

28

3.2 Linear Measurernents

Fig.

8)

Fig.

28. The

principal

inearmeasurementssed

n the analysis.

44

U

U,I


46/224

We also

measure

he following

inear distances.

No. Distance Definition

Mean

value

1

S-N

2

S-Ar

3

S-Go

4

N-Me

5

MaxBase

6

ManBase

7

R.asc.

8

S'-F.Ptp.

S-S'

1-N-Pog

T-N-rog

(SeN)

Anteroposteriorextent

of

anterior

cranial

base

Extent of lateral

cranialbase

Posterior

facial height

Anterior facial height

Extent

of

maxillary

base,

correlated

with

Se-N

(see

Table

4,

page

62)

Extent

of

mandibular

base,correlated

with

SeN

Extent

of

ascendingamus,correlated

with

SeN

Distance rom

S' to

projection

of the

anterior

wall

of the

pterygopalatinal

ossa

onto the palatal

plane,

expressionor anteroposterior

displacement

of the

maxillary

base

Expression

or

deflections

of the

maxillary

base 42-57

mm

Distance rom incisaledge

of

L

to N-Pog

ine

Distance rom incisaledgeof T

to N-Pog

ine

71mm

32-35mm

9

10

11

It is

not

absolutely

necessaryn

practice

to

use

hyphens

between

he.points

used

o

define ines

and angles,

e.g. N-Pog

=

NFog, S-N-MeGo

=

SN-MeGo.

45


47/224

29

Significance

f

Angular

and

Linear

Measurements

or

D

ento-Skeletal

nalYsis

Dento-skeletal

analysis

n

norma

ateralis

s carried

out

in

three

stages:

(1)

Analysis

of

facial

skeleton

(2)

Analysis

of

mandibular

and

maxillary

base

(3)

Dento-alveolar

nalYsis

Analys

thomas rakosi cefalometrie

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