the clinical relevance

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Clinical Paper

Orthognathic Surgery

The clinical relevance oforthognathic surgery on qualityof lifeC. Murphy, G. Kearns, D. Sleeman, M. Cronin, P. F. Allen: The clinical relevance oforthognathic surgery on quality of life. Int. J. Oral Maxillofac. Surg. 2011; 40: 926930.# 2011 International Association of Oral and Maxillofacial Surgeons. Publishedby Elsevier Ltd. All rights reserved.

C. Murphy1, G. Kearns2,D. Sleeman1, M. Cronin3,P. F. Allen1

1Department of Oral and MaxillofacialSurgery, Cork University Dental Hospital,Ireland; 2Department of Oral and MaxillofacialSurgery, Mid-Western Regional HospitalLimerick, Ireland; 3Department of StatisticsUniversity College Cork, Ireland

Abstract. The aim of orthognathic surgery is to produce a more aesthetic facialskeletal appearance, and improve jaw function. This prospective study, aimed toevaluate the impact of orthognathic surgery on quality of life for patients withdentofacial deformity, and whether it was clinically meaningful. 62 consecutivepatients were recruited (27 male, 35 female) aged 1838 years. Baseline data werecollected using a validated health status measure (Orthognathic Quality of LifeQuestionnaire (OQLQ)) and a visual analogue scale (VAS). Postoperativequestionnaires (OQLQ, VAS) and a Global Transition Scale (GTS) were completedat 6 months after completion of treatment and compared with pre-treatment scores.Following surgery, there was a significant (p < 0.05, pairedt test) improvement inOQLQ scores for each domain. The proportion of patients reporting a moderate orlarge improvement was: facial appearance (93%), chewing function (64%), comfort(60%) and speech (32%). Clinical relevance of change scores was reported in termsof effect sizes, and the largest effect was on facial aesthetics. The clinical impactwas moderate on social aspects of deformity and oral function and a small effect onawareness of facial deformity. This research reaffirms that orthognathic surgery haspositive effects on quality of life.

Key words: orthognathic surgery; quality of life.

Accepted for publication 8 April 2011Available online 26 May 2011

The evaluation of quality of life usinghealth status measures is increasing inthe assessment of healthcare outcomes1,21.It has been recognized that objective mea-sures alone do not fully capture the impactof a condition on daily living, and sub-jective assessment of the impact of diseaseor condition is also required.

Orthognathic surgery is carried out tocorrect dentofacial deformity. Thisinvolves pre-surgical orthodontics withfixed appliances for alignment and level-

ling of the dental arches. Surgery is thencarried out to reposition the jaws, resultingin a moreharmonious facialskeleton.Manystudies show that patients benefit psycho-logically and have improved facial anddental aesthetics and improved functionafter treatment8,10,11,14,15,19,20,22.

The assessment of quality of life impactafter orthognathic surgery is difficult tomeasure objectively as the patients lifeis neither extended nor is a disease curedin the conventional understanding of

healthcare1. Health related quality of life(HRQoL) is multifactorial, and any modelconstructed to quantify this should include,physical, social and psychologicaldomains, as suggested by CAMILLERI-BREN-NAN & STEELE3. Generic health, generic oralhealth and condition-specific measureshave been used to assess the impact oforthognathic surgery. The generic healthquestionnaire may be used to compare theoutcomes with those of other conditions,but the lack of condition specificity can

Int. J. Oral Maxillofac. Surg. 2011; 40: 926930doi:10.1016/j.ijom.2011.04.001, available online at http://www.sciencedirect.com

0901-5027/090926+ 05 $36.00/0 # 2011 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.ijom.2011.04.001http://dx.doi.org/10.1016/j.ijom.2011.04.001http://dx.doi.org/10.1016/j.ijom.2011.04.001http://dx.doi.org/10.1016/j.ijom.2011.04.001


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mean that generic instruments are not ableto address issues relevant to people withfacial deformity. For instance, LEE et al.16

found the 36 item Short Form Health Sur-vey (SF-36) to be insensitive and unable todetect differences in quality of life betweenthose with and without dentofacial defor-mities.

The development of a condition-speci-fic measure was undertaken to generate aspecific measure that could focus on aparticular condition and population andbe potentially more responsive to small,but clinically important, changes inhealth6,7. CUNNINGHAM et al.6 noted thatpatients with severe dentofacial deformityhad not been studied in this way andprevious reports relied on generic ques-tionnaires that were less likely to detectspecific changes in a specific population.The Orthognathic Quality of Life Ques-tionnaire (OQLQ) was developed using

several sources for item derivation,including a literature review, and unstruc-tured interviews with clinicians andpatients6,7.

The items were divided into fourdomains: social aspects of deformity,facial aesthetics, oral function and aware-ness of facial deformity. CUNNINGHAMet al.

6have tested the validity of OQLQ

by using the SF-36 questionnaire and avisual analogue scale (VAS) for compar-ison. A number of recent reports have usedthe OQLQ to evaluate the impact oforthognathic surgery on quality of life.

In a casecontrol study of 154 Chinesepatients, LEE et al.16 showed that facialdeformity affects many aspects ofpatients lives and the OQLQ was ableto detect this. In a follow up publication,36 of these patients received orthognathicsurgery and reported significant improve-ment in quality of life

15. In a study of

German patients using the OQLQ, BOCKet al.2 confirmed the findings of LEE et al.that facial deformity had significant nega-tive impacts on quality of life. Each ofthese reports suggests that the OQLQ hasgood measurement properties and is sui-table as an outcome measure for facialdeformity and its management usingorthognathic surgery.

Measurement of change is central toevaluating the impact of treatment inhealthcare, and is usually reported in termsof statistical significance. In some cases,pre-/post-treatment change scores may bestatistically significant but not necessarilyclinically significant or meaningful to thepatients who experience that change.Interpretability of a health status measurehas been defined as the degree to whichone can assign qualitative meaning that

is, clinical or commonly understood con-notations to quantitative scores18. Acommonly used approach to determinethe clinical meaning of scores is to calcu-late the effect sizes. An effect size is adistribution based measure of change, andCOHEN4 has suggested benchmarks to indi-cate the size of change that has occurred

following a clinical intervention. He hassuggested that an effect size of 0.2 isequivalent to a small change, 0.30.7 asa moderate and>0.8 as a large pre-/post-treatment change.

None of the previous studies have usedself reported global transition scores togive an indication of the clinical relevanceof orthognathic surgery, nor have theyattempted to quantify the clinical rele-vance of change. The aim of this studywas to evaluate the impact of orthognathicsurgery on the quality of life of patientswith facial deformity, and, to determine if

the OQLQ is able to detect clinicallyimportant change in patients undergoingsurgery to correct dentofacial deformity.

Material and methods

The study protocol was reviewed andapproved by the Clinical Research Ethicscommittee of the Cork Teaching Hospi-tals. Patients attending for consultation inorthognathic surgery between June 2006and July 2008 in Cork and Limerick max-illofacial surgery units were asked to par-ticipate. In this prospective study, 62

consecutive patients (27 male, 35 female)with congenital deformities in the maxilla,mandible or both, agreed to participate inthe study. All of the patients had conge-nital disharmony, and none of them hadsymptoms associated with syndromes.The age range was 1838 years (mean21.6 years). Patients were recruited havingcommenced orthodontic treatment, andwhilst awaiting surgical treatment. Datawere collected at two stages: during theorthodontic phase of treatment, prior tosurgical intervention; and 6 months aftersurgical treatment. The measures used toassess quality of life were the OQLQ, aVAS and, a Global Transition Scale(GTS). Patients completed the OQLQand VAS prior to treatment, and thepost-treatment questionnaire 6 monthspost-surgery. The GTS was included inthe post-treatment questionnaire, and usedto determine the concurrent validity of thepre- and post-treatment change score forthe OQLQ.

The OQLQ contains 22 statementsrelating to 4 domains: appearance; func-tion; social aspects of deformity; andawareness of deformity. Respondents are

asked to indicate their level of agreementwith statements such as I dont like eatingin public places. These responses arerated on a Likert scale scoring system,with response possibilities ranging from1 (it bothers you a little) to 4 (it bothersyou significantly). Summary scores foreach domain were calculated by summing

response codes within domains pre- andpostoperatively and then compared todetect change. Higher scores indicatehigher levels of concern in relation to eachdomain, lower scores indicate less concernand better quality of life.

A VAS was also incorporated into thepre- and post-treatment questionnaires.Patients were asked to indicate their levelof satisfaction with treatment on a 100 mmscale ranging from 0 to 100, 0 being poorsatisfaction level and 100 being the bestpossible outcome. The preoperative VASwas rated on satisfaction with treatment up

to the point of surgery. The postoperativeVAS was rated on satisfaction with post-surgery period and outcomes of treatment.

In addition, a GTS was incorporated inthe post-treatment questionnaire to pro-vide an anchor based measure of changeagainst which the condition-specific scalecan be measured. In this questionnaire,patients rated the impact of surgery onappearance, chewing, oral comfort andspeech. As recommended by JUNIPERet al.13, these transition variables werescored on 15-point scale (Table 1).

In addition to descriptive statistics, pre-

treatment domain scores were comparedwith post-treatment scores using paired ttests (SAS1 Version 9.1) at a 5% level ofsignificance. Effect sizes for each domainwere calculated by subtracting the meanpost-treatment score from the mean pre-treatment score and dividing by the stan-

Clinical relevance of orthognathic surgery on quality of life 927

Table 1. Global Transition Scale responsepossibilities.

Code Response

1 A very great deal worse2 A great deal worse3 A good deal worse

4 Moderately worse5 Somewhat worse6 A little worse7 Almost the same,

hardly any worse at all8 No change9 Almost the same,

hardly anybetter at all

10 A little better 11 Somewhat better 12 Moderately better 13 A good deal better 14 A great deal better 15 A very great deal better


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dard deviation of the pre-treatment score.Using the Global Transition Scale, theproportion of patients who reported nochange, minor improvement, moderateimprovement, large improvement anddeterioration were calculated. Also, fol-lowing JUNIPER et al.13, the magnitude ofchange in the four domains assessed wasdefined as follows: 7, 8 or 9 was consid-ered as no change; 10 or 11 was consid-ered as a small change that defines the

minimally important difference; 12 or 13was considered moderately changed; 14 or15 was considered a large change; and 1,2, 3, 4, 5 or 6 was considered a deteriora-tion.

Results

There were 62 participants in the study ofwhom 52 completed postoperative ques-tionnaires. 10 subjects (5 male, 5 female)were lost to follow-up, but there were nocharacteristic differences between thesepatients and those who completed the

follow-up questionnaires. For the remain-ing 52 patients, the most common skeletalclassification was class 3 (n = 32). Thiswas corrected by mandibular setback orbimaxillary surgery. 16 patients had sur-gery to correct class 2 malocclusion, 4patients had surgery to correct class 1malocclusion. All of the patients in thestudy, except one (female, age 36 years),had pre-surgical orthodontic treatment tooptimize treatment outcome. Mean lengthof time for pre-surgical orthodontics was24 months.

The mean pre-/post-treatment differ-

ence was found to be statistically signifi-cant for all domains of the OQLQ at the5% level of significance (Table 2). In

terms of clinical significance, the effectssizes were: appearance 0.9; function 0.4;social aspects of deformity 0.4, and aware-ness of deformity 0.2. This indicates thatthe impact on appearance was large, withmoderate impacts on social aspects ofdeformity and function. The impact onawareness of deformity was clinicallyimportant, but the effect was small. Thepreoperative VAS scores are high, whichmay be attributed to the fact that patients

are satisfied with orthodontic treatmentand surgical consultations. The mean dif-ference in VAS is statistically significantas shown in Table 2.

In terms of the post-treatment GTS,details of the change in scores for eachcategory are shown in Table 3. Overall,the most patients reported improvement inall four domains. The level of reportedimprovement varied from minor improve-ment to large improvement. Orthognathicsurgery appears to have the biggest impacton appearance and chewing, followed bycomfort. Its impact on speech is much less,

and unlikely to be clinically meaningful(32 patients reported no change in thisdomain).

Discussion

The analysis of change in quality of lifewas carried out using the OQLQ. Thiscondition-specific questionnaire was con-structed to tap into the various areas ofconcern for patients and show if there wasa quantifiable change as result of surgery.The mean difference score in each domainshowed a statistically significant change,

and this may reflect areas of improvementin relation to appearance and psychologi-cal benefits such as having improved self

confidence in public. There was also asignificant improvement in function forthe study population. This may reflectimprovement for such groups with signif-icant reverse overjets or anterior openbites. The clinical relevance of theseeffects varied, and it would appear, asone could reasonable expect, that the lar-

gest impact was on appearance. Theimpact of orthognathic surgery on socialand functional domains was important, butmore moderate than its impact on percep-tion of appearance. There could be anumber of explanations for this, includingthe variation in patient personality and theage range of the sample. A further possi-bility is that significant facial appearancechange is immediate and dramatic, andthus the most obvious impact followingsurgery. Such a significant facial appear-ance change may make some patientscautious about engaging in social interac-

tion in theimmediate aftermath of surgery,and thus moderate the impact on thesedomains. It is possible that this mayimprove with time as the patient becomesmore confident with social interactionpost-surgery. This finding is of relevancewhen explaining the possible benefits topatients with facial deformity in advanceof surgery.

The majority of studies previously car-ried out were retrospective and showed asimilar correlation with the presentresults

1417The longitudinal studies car-

riedout by KIYAK et al.14

and CUNNINGHAM

et al.5

also revealed high satisfaction rates.The results from this prospective studycompare favourably, as the majority ofpatients reported improved perception ofappearance, function and self confidence.

The GTS was completed by patientspostoperatively to measure the effect ofsurgery on appearance, chewing, speechand oral comfort. It also allowed the con-struct validity of the OQLQ to be tested.Perceived chewing ability improved formost patients, with 56% of the samplereporting moderate or large improvementas a result of surgery. A significant similarpicture emerged for the impact of surgeryon appearance, with 81% of the samplereporting a moderate or large change. A

928 Murphy et al.

Table 2. Comparison of mean pre-/post-treatment OQLQ scores (by domain) and VAS scores(n = 52).

Domain, N= 52 Mean pre (S.D.) Mean post (S.D.) Mean difference P-value

Aesthetics 12.21 (5.87) 7.00 (5.64) 5.21 (6.19) 0.0001*

Awareness 6.90 (4.80) 5.73 (4.19) 1.17 (3.93) 0.0363*

Social 10.42 (8.33) 7.19 (8.32) 3.23 (8.18) 0.0063*

Function 7.46 (5.99) 5.69 (5.77) 1.77 (6.00) 0.0384*

VAS (N= 41) 79.22 (18.42) 87.56 (15.50) 8.34 (20.94) 0.0*

* Statistically significant p < 0.05, paired t tests.

Table 3. Global rating of post-treatment change, by domain, reported as proportion (percentage) of sample (n = 52) in each change category.

DomainGlobal transition rating

Deterioration(1, 2, 3, 4, 5, 6)

No change(7, 8, 9)

Minor improvement(10, 11)

Moderate improvement(12, 13)

Large improvement(14, 15)

Appearance 0 (0%) 4 (7%) 6 (12%) 18 (35%) 24 (46%)Chewing 4 (7.5%) 15 (29%) 4 (7.5%) 13 (25%) 16 (31%)Comfort 8 (15%) 13 (25%) 8 (15%) 11 (22%) 12 (23%)Speech 2 (4%) 32 (62%) 4 (7%) 5 (10%) 8 (15%)


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significant proportion of patients cite func-tion and appearance as their motivation fortreatment. FINLAY et al.9 suggested thatfacial appearance was cited by 52% ofpatients as the most important reason forundergoing surgery, whilst 31% citedfunction as the most important reason.These results are similar to those found

by WILMOTT et al.23 which also suggestedfigures of 56% citing aesthetics and 32%citing difficulty chewing. One of the pos-sible benefits of GTS is that it capturesinformation about people who did notimprove or deteriorated post-surgery.The results in the present study suggestthat 7% of patients reported a deteriorationin function. This may be attributed to thefact that some patients had not completedpost-surgery orthodontics at the time ofpost-treatment evaluation. 15% of thesample reported a deterioration in comfortfollowing surgery, which is potentially

related to surgical side-effects such asaltered sensation. To determine whetherthis is a transient effect would require alonger follow-up period. The results sug-gest that orthognathic surgery has a lim-ited impact on speech. A small proportionof patients reported improved speech andthis may be due to improved occlusalharmony and improved lip competence.Surgery is not aimed at correcting speech,but improvements in this area are consid-ered an added benefit from surgery. TheGTS also reported deterioration in a smallpercentage of patients in chewing, comfort

and speech components, which may bedue to the timing of follow-up as patientsare still readjusting to post-surgicalchanges. The authors would not anticipatethese findings to be significant in the longterm.

These results reaffirm those obtainedusing the OQLQ and may be used to showits responsiveness as a condition-specifictool. As highlighted in a recent systematicreview12, variations in study design andlack of uniformity of approach in asses-sing psychosocial constructs haveobscured the true nature of the impactof orthognathic surgery. The items inthe OQLQ may be considered representa-tive of areas of interest for these patients,but the GTS would be recommended foruse alongside OQLQ in future longitudi-nal studies. In addition, it may ultimatelybe used to determine the minimally impor-tant clinical difference for the OQLQmeasure.

The patients main point of dissatis-faction was the length of treatment andoccasional cancellation of surgery.Length of treatment time presurgerywas 23 months, which, which should

be considered satisfactory when onetakes into account the waiting time forsurgery once orthodontic treatment iscompleted. A small number of patientsrequired orthodontics for more than 4years; this was due to a change in thetreatment plan from orthodontics only tocombined surgery and orthodontics. This

may be avoided in the future by earlyrecognition of deformity beyond thescope of orthodontics. It may also indi-cate that early referral of patients to amultidisciplinary clinic would be desir-able.

This is close to an acceptable timeframe as orthodontic treatment mayoften take 18 months to 2 years forstandard fixed appliance therapy. Anumber of patients were treated for 34 years, owing to alteration of treatmentplans or waiting for hospital beds onceorthodontic decompensation was com-

pleted. One patient had pre-surgicalorthodontics for 108 months due tochanging treatment plans.

In conclusion, combined orthodonticsand orthognathic surgery is a reliabletreatment modality with significant posi-tive effects. This is the first longitudinalstudy carried out in an Irish populationwith dentofacial deformity. Overall theresearch shows a positive impact on thepatients facial appearance and oral func-tion and found social advantages such asimproved self confidence.

Funding

None.

Competing interests

None declared.

Ethical approval

Ethical approval was granted from EthicsResearch committee at Mid WesternRegional Hospital Limerick and Cork

University Hospital.

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Postal address:C. Murphy

Department of Oral and MaxillofacialSurgery Cork University Dental School and

Hospital WiltonCork

IrelandTel: +00353 868239161E-mail: [email protected]

930 Murphy et al.
mailto:[email protected]:[email protected]

the clinical relevance

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