Orthognathic Treatment and Temporomandibular
Orthognathic Treatment and Temporomandibular
Orthognathic Treatment and Temporomandibular
Introduction: There have been conflicting viewpoints in the literature regarding the effects of orthognathic
treatment on temporomandibular disorders (TMD). A systematic review was conducted to determine the per-
centage of orthognathic patients with TMD, establish the range of signs and symptoms, and follow patients
longitudinally through treatment for any changes in signs and symptoms. Methods: Part 1 of this 2-part article
described the methodology of this review, with a narrative analysis of the study characteristics and the TMD
classification methods. Part 2 describes the percentage of patients suffering from TMD and the signs and
symptoms reported. Meta-analyses were conducted on data from clinically similar studies. Results: Pain de-
creased after surgery for both self-reported symptoms and clinically diagnosed pain on palpation. However,
postsurgical results were more varied for joint sounds. The percentage of patients with clicking had a tendency
to decrease postsurgery, but improvements in crepitus were questionable. The results from all meta-analyses
in this review were subject to considerable statistical heterogeneity, and it was not possible to draw strong
inferences relating to the percentage of orthognathic surgery patients with TMD with any degree of certainty.
Conclusions: Although orthognathic surgery should not be advocated solely for treating TMD, patients having
orthognathic treatment for correction of their dentofacial deformities and who are also suffering from TMD ap-
pear more likely to see improvement in their signs and symptoms than deterioration. (Am J Orthod Dentofacial
Orthop 2009;136:626.e1-626.e16)
F
unctional and esthetic considerations often A systematic review was conducted to determine the
prompt patients to seek orthognathic treatment percentage of orthognathic patients with signs and
to correct jaw discrepancies; this involves a com- symptoms of TMD, and to establish the range of signs
bination of orthodontics and surgery. Yet it has been re- and symptoms. In addition, we examined studies that
ported that orthognathic surgery can introduce unwanted followed patients longitudinally throughout treatment
alterations in the temporomandibular joint (TMJ), giving to determine whether intervention to correct skeletal
rise to temporomandibular dysfunction (TMD).1 discrepancies affects TMD signs and symptoms. After
There are few high-quality studies in the field of an extensive search strategy and full-text screening, 53
TMD research that attempt to reduce bias, and there articles fulfilled the criteria for inclusion in this review.
are even fewer high-quality articles regarding the asso- Analysis of the results of systematic reviews can be
ciation between major skeletal disharmonies and their narrative or quantitative (involving statistical analysis).
effects on TMD.2 If the bearing of orthognathic treat- Although often associated with quantitative analysis, it
ment on TMD is considered, the viewpoints include is acceptable for a systematic review not to contain
that orthognathic intervention might induce or resolve a meta-analysis.5 The results of this review were pre-
TMD, or have little or no effect on TMD.3,4 dominantly narrative, and we used subjective rather
than statistical methods to determine the direction of
From the UCL Eastman Dental Institute, London, United Kingdom.
a
Postgraduate student, Orthodontic Unit. the effect, the approximate size of the effect, whether
b
Senior lecturer/honorary consultant, Orthodontic Unit. the effect was consistent across studies, and the strength
c
Former lecturer, Health Services Research; professor of Oral Health Services of evidence for the effect. This was carried out because,
Research, director of Postgraduate Education and Research, Peninsula Dental
School, Plymouth, United Kingdom. for most of the studies, a statistical analysis was either
The authors report no commercial, proprietary, or financial interest in the prod- not feasible (eg, because of differences in the choices
ucts or companies described in this article. of outcome measures between studies) or inappropriate
Reprint requests to: Salma Al-Riyami, Orthodontic Unit, UCL Eastman
Dental Institute, 256 Grays Inn Rd, London WC1X 8LD, United Kingdom; (eg, because of substantial clinical heterogeneity).
e-mail, s.alriyami@eastman.ucl.ac.uk. Meta-analysis is a statistical analysis of the results
Submitted, October 2008; revised and accepted, February 2009. from independent studies; it generally aims to produce
0889-5406/$36.00
Copyright Ó 2009 by the American Association of Orthodontists. a single estimate of effect.6 This should be carried out
doi:10.1016/j.ajodo.2009.02.022 only after assessing the methodologic quality of the
626.e1
626.e2 Al-Riyami, Cunningham, and Moles American Journal of Orthodontics and Dentofacial Orthopedics
November 2009
studies and only if there is sufficient homogeneity to of the effects, and its width describes heterogeneity.
warrant pooling the studies’ estimates. Studies to be Finally, the standard error of the pooled treatment
pooled should ideally be free from clinical and method- effect or effect size was used to calculate a confidence
ological diversity (eg, using different classification sys- interval that indicates the precision of the pooled
tems for recording TMD). Meta-analysis is a 2-stage estimate.7,17
process involving the calculation of an appropriate sum- For this study, random-effects meta-analyses were
mary statistic for each of a set of studies followed by conducted by using the statistical program Stata (ver-
combining these statistics into weighted averages. The sion 10.1, Stata Corp, College Station, Tex).
selection of a meta-analysis method should take into ac-
count data type, choice of summary statistics, observed
heterogeneity, and known limitations of the computa- RESULTS
tional methods.7 The percentages of patients with self-reported
symptoms are shown in Table II. Of the 53 studies,
only 18 presented information regarding the symptoms
MATERIAL AND METHODS reported by patients.
The methodology for conducting the systematic re- In the 4 studies that followed subjects longitudi-
view, including focused questions, criteria for inclusion nally, the percentages of subjects reporting joint sounds
of studies, search strategy, data extraction, and quality as- decreased after surgery in 2 studies: from 28% to 3%13
sessment, were described in Part 1 of this study. Part 2 fo- and from 24% to 20%.18 The prevalence of joint sounds
cuses on the remaining results, the evidence tables, and remained the same in 1 study at 30%19 and increased in
the methods involved in conducting the meta-analyses. another study from 38% to 43%.20
Most of the included studies did not use a validated Painful symptoms commonly reported by patients
scale to measure TMD, so it was not appropriate to in- included TMJ, jaw, face, and muscle pain. In the 3
clude them in a meta-analysis because of heterogeneity studies that reported both presurgical and postsurgical
in the assessment of TMD. Meta-analyses were carried results, the percentages of patients reporting TMJ
out on only the 12 studies that used the Helkimo index8 pain decreased after surgery.13,18,21 A similar trend
to classify TMD in patients at presurgery and postsur- was seen with jaw, face, and muscle pain. The per-
gery (Table I). centages of patients experiencing headaches were
Although the patients in these studies had differing lower after surgery in the 6 studies that provided
combinations of skeletal deformities and malocclu- this information.
sions, and had received various orthognathic interven- Clinical TMD signs are given in Table III. In studies
tions, there was sufficient homogeneity to carry out that presented both presurgical and postsurgical clinical
a meta-analysis on (1) the percentage of patients af- data, there was a tendency for the percentages of pa-
fected by TMD presurgery (of the 12 studies identified, tients affected by joint clicking to decrease after surgery
7 were eliminated because of incomplete or duplicated (in 22 of 24 studies). Only 2 studies found higher per-
data, and thus only the 5 studies with complete preoper- centages of patients with clicking after surgery.11,22
ative results were pooled)9-13; (2) patients with skeletal With regard to crepitus, the findings were varied.
Class II deformity having bilaterial sagittal split osteot- Some studies reported decreases in crepitus after sur-
omy (BSSO) advancement procedures9,10,13; and (3) pa- gery,11,13,23,24 whereas others reported that it either
tients with vertical maxillary excess (VME) having remained the same9,25,26 or increased.12,27,28
LeFort 1 maxillary impaction procedures14,15 (although The percentage of patients affected by TMJ pain on
the vertical relationships of the patients in these sub- palpation decreased after surgery in 14 of 18 studies.
groups were not specified). However, pain increased in 3 studies29-31 and remained
The basic principles of conducting a meta-analysis, the same in 1 study.32 Muscle pain on palpation was also
as described by the Cochrane Handbook, were fol- a commonly reported TMD symptom, and, when the
lowed.16 A summary statistic was calculated for each presurgical and postsurgical findings were compared,
study; it described the treatment effects or the effect 9 of 11 studies showed decreases in the percentages of
size. A pooled treatment effect estimate or effect size patients affected by muscle pain after surgery. Only 1
estimate was then calculated as a weighted average of study31 reported an increase in symptoms, and another
the treatment effects. Random-effects meta-analyses found that it remained the same.33
were undertaken. This assumes that each study is esti- Maximal incisal opening decreased after surgery, but
mating different treatment effects. The center of this there was a tendency for this to improve with time. Gaggl
symmetric (normal) distribution describes the average et al23 reported maximal incisal openings of 47.5 mm
American Journal of Orthodontics and Dentofacial Orthopedics Al-Riyami, Cunningham, and Moles 626.e3
Volume 136, Number 5
*Helkimo’s dysfunction index: Di0, no dysfunction; Di1, mild dysfunction; Di2, moderate dysfunction; Di3, severe dysfunction; †Helkimo’s anam-
nestic index: Ai0, no symptoms; Ai1, mild symptoms; Ai2, severe symptoms; ‡Helkimo’s mandibular mobility index: Mi0, normal mobility;
Mi1, mild impairment; Mi2, severely impaired; §Percentages are approximate and were taken from the graph in the published article.
Percentages (rounded up) of patients with self reported TMD symptoms
626.e4
Table II.
November 2009
Preop, Before surgery; postop, after surgery; preortho, before orthodontic treatment; N/R, not reported.
*Visual analog scale rating; †oral health status questionnaire (1, mild; 7, extreme); ‡unclear whether findings reported are from clinical examination or patient questionnaire.
Clinical findings of TMD signs
626.e6
Table III.
November 2009
1988 1-4 y postop 4 2 1
Rodrigues-Garcia Preop 49 14 5
et al, 1998 2 y postop 24 8 15
Schearlinck et al, Preop 46.8
1994 1 y postop 6 13 45.8 2
Continued
MIO, Maximal incisal opening (mean, unless a range is given); Preop, before surgery; postop, after surgery; preortho, before orthodontic treatment; pre-Rx, pretreatment; N/S, not specified; N/R,
not reported; N/A, not applicable; IMF, intermaxillary fixation surgical group; RF, rigid fixation group; SP, straight plate; BP, bent plate; R, records; CE, clinical examination; RHS, right-hand
presurgery and 35.5 mm 3 months postsurgery, but stud- 68%9 after surgery. The percentages of moderate dys-
ies with a longer follow-up, such as that of Borstlap function ranged from 7%13 to 75%11 before surgery,
et al,30 showed a more modest reduction from 46.4 mm and 5% and 54% after surgery, respectively. Few studies
before surgery to 45.6 mm 2 years after surgery. reported patients with severe dysfunction (n 5 3). In 4
The percentages of patients with confirmed TMD at studies, the percentage of patients with mild dysfunc-
various time intervals are shown in Table IV. A positive tion increased after surgery, whereas the percentages
diagnosis of TMD in presurgery patients varied between of patients with moderate or severe dysfunction showed
7% and 78%.12,34 In the 18 longitudinal studies with fol- a tendency to decrease after surgery (n 5 5).
low-up data, the postoperative prevalence of TMD var- Only 4 studies also recorded the anamnestic in-
ied. The percentages of patients affected by TMD dex.9,11,13,14 The results for this component of the Hel-
decreased in most (n 5 12) studies. This decrease in kimo index varied between studies, but the percentages
TMD was marked in some studies: from 43% to 28%13 of patients with severe symptoms decreased after sur-
and from 73% to 48%,18 and less in others—from 66% gery in those 4 studies.
to 62%.10 TMD prevalence remained the same in 1
study33 and actually increased in 6 studies.3,14,15,20,27,31 Meta-analyses
This increase was marked in some studies: from 36% to As stated in the methodology, because of the few stud-
84%3 but less in others—40% to 45%.20 ies included and the high variability of their estimates,
Change in TMD signs and symptoms are given in random-effects meta-analyses were used in this study.
Table V. Thirty-five studies reported changes in TMD. The percentages of orthognathic patients with TMD
There was, however, great variability in the signs and before surgery are shown in Table VI. The random-ef-
symptoms investigated in the studies. The initial time fects pooled estimate of TMD prevalence before surgery
point for most studies was presurgery, although in 2 for the studies was 74% (95% CI, 57%-92%) (Table VI,
studies it was before orthodontic treatment.11,35 Subse- Fig 1). The forest plot7 shows statistically significant be-
quent follow-up time intervals ranged from 6 months af- tween-study variations in the percentages of patients af-
ter surgery to more than 9 years.36 There was little fected by TMD before surgery (Fig 1). The greatest
consistency in the changes in TMD signs and symptoms weight was given to the study of Panula et al,11 with an
during the follow-up intervals. Only 13 studies reported estimate of 97% (95% CI, 92%-100%).
whether patients who were asymptomatic before sur- Information on patients with skeletal Class II defor-
gery developed new signs and symptoms after surgery; mity having BSSO advancement procedures is presented
this ranged from 4%37 to 35%.14 in Table VII. There were significant between-study var-
The percentages of patients who had improvements iations in the reported percentages of presurgery patients
in signs or symptoms ranged from 6%21 to 89%,4 and affected by TMD in the 3 Class II mandibular advance-
5%38 to 41%14 had worse TMD signs and symptoms. ment studies.9,10,13 Significant between-study variations
In most studies that reported whether symptoms got bet- were also found for the percentages of TMD postsurgery
ter, worse, or remained the same, the percentages of pa- and overall changes after treatment. The forest plots of
tients whose symptoms improved (18 studies of 23) the percentages of patients with TMD before and after
outweighed those whose symptoms worsened (4 of surgery are shown in Figure 2, A and B. The change in
23). In patients who had TMD signs and symptoms in the percentage of patients affected by TMD is shown
the initial time period, the percentages whose symptoms in Figure 2, C. Figure 2, A, shows that the pooled
remained the same ranged from 3%4 to 67%.9 meta-analysis effect corresponds to a preoperative
TMD findings in studies that used the Helkimo in- TMD percentage of 59% (95% CI, 35%-84%), and Fig-
dex are shown in Table I. Twelve studies classified ure 2, B, shows a pooled postsurgery percentage of 72%
TMD according to the Helkimo or the modified Hel- (95% CI, 40%-100%). Figure 2, C, indicates a pooled
kimo, index. The percentages of patients with no dys- change in the percentage of patients affected by TMD
function preoperatively ranged from 4%11 to 43%.13 of 16% (95% CI, –9%-41%). This point estimate corre-
After surgery, these changed to 8% and 58%, respec- sponds to an increased prevalence of the condition but
tively. In 4 studies where a before-and-after comparison was not statistically significant (P 5 0.216).
was possible, the percentage of patients with no dys- Information on patients with VME undergoing
function increased after surgery. It remained the same LeFort 1 maxillary impaction procedures is given in
in 1 study33 and decreased in 2 studies.9,15 Table VIII. Only 2 studies were included in this meta-
When mild dysfunction was considered, the per- analysis. The meta-analysis for the postsurgical data is
centages of patients affected ranged from 13%11 to shown, and the pooled estimate for the studies was
58%33 before surgery, and between 38%11,13 and 68% (95% CI, 52%-84%). It was not possible to carry
American Journal of Orthodontics and Dentofacial Orthopedics Al-Riyami, Cunningham, and Moles 626.e9
Volume 136, Number 5
Table IV. Patients with confirmed TMD at various time intervals (percentages were rounded up)
Preortho Presurgery \6 mo postop $6 mo postop $1 y postop $2 y postop
Author, year (%) (%) (%) (%) (%) (%)
out a meta-analysis on the preoperative data or to esti- surgery in their self-reports, and no conclusive trend
mate the change after treatment because the preopera- was observed with regard to these symptoms.
tive results in the study of Little et al14 were not The patients’ perception was that pain tended to
reported. Figure 3 shows that the estimates for both improve after surgery. For almost all types of pain
studies (71% and 65%) were similar to the pooled reported (TMJ, jaw, muscles, face), there was a ten-
meta-analysis estimate of 68% (95% CI, 52%-84%). dency for the percentages of patients with reported
However, only 2 studies contributed to these results. pain to decrease after surgery. This was also true for
headaches. It is unclear whether this is a genuine
effect caused by changes in the joint as a result of
DISCUSSION the surgery or a placebo effect because of the patients’
There was great variability in the percentages of altered outlook. Although a placebo effect in patients
patients who noted improvement in joint sounds after undergoing orthognathic interventions has not been
Change in TMD signs and symptoms
626.e10
Table V.
Initial time Affected Follow-up time Affected Same Better Worse New symptoms/
November 2009
N 5 23
Little et al, 1986 TMD Preop 47 1.4-4.7 y postop 59 6 n 5 1 35 n 5 6 41 35
n58 n 5 10 n57 n56
N 5 17 N 5 17
Continued
Initial time Affected Follow-up time Affected Same Better Worse New symptoms/
Author, year Sign/symptom interval (%) interval (%) (%) (%) (%) signs (%)
Preop, Before surgery; postop, after surgery; preortho, before orthodontic treatment; N/R, not reported.*When possible, percentages were reported; otherwise, n, number of patients affected; N, total
patients in group.
626.e12 Al-Riyami, Cunningham, and Moles American Journal of Orthodontics and Dentofacial Orthopedics
November 2009
Study estimate/
Study/method pooled estimate Lower Upper
Table VII. Heterogeneity test and meta-analysis for patients with skeletal Class II deformity having BSSO
Proportion of skeletal Proportion of skeletal
Class II patients Class II patients Change in proportion of TMD pre- and
with TMD presurgery with TMD postsurgery postsurgery in skeletal Class II patients
Athanasiou and 0.33 0.07 0.60 0.83 0.62 1.04 0.50 0.16 0.84 N/A
Yucel-Eroglu,
1994
Kallela et al, 2005 0.57 0.42 0.73 0.43 0.27 0.58 –0.01 –0.23 0.20 N/A
Smith et al, 1992 0.82 0.66 0.98 0.91 0.79 1.03 0.09 –0.11 0.29 N/A
Pooled (random) 0.59 0.35 0.84 0.72 0.40 1.04 0.16 –0.09 0.41 0.22
Test for Q 5 10.500 on 2 degrees Q 5 24.721 on 2 degrees Q 5 6.378 on 2 degrees
heterogeneity of freedom (P 5 0.005) of freedom (P \0.001) of freedom (P 5 0.041)
*A positively signed change estimate indicates that the proportion of patients with TMD is increasing.
N/A, Not applicable.
explored, it has been studied in medicine. Turner to the progression of the patient to a worse condition
et al39 reviewed the literature to investigate the impor- of disc displacement without reduction. This condition
tance and implications of placebo effects in pain is often accompanied by a reduction in mouth opening,
treatment. They found that placebo response rates but this was difficult to assess from the articles with the
vary greatly and are frequently much higher than the level of detail that they provided. Magnetic resonance
often-cited one third, and, as with medication, surgery imaging would address this conflict, but unfortunately
can also produce substantial placebo effects. They only 2 studies used this.23,40 Encouragingly, the results
concluded that placebo effects influence patient from these studies indicated that the joints with dis-
outcomes after any treatment, including surgery, which placed discs were more likely to show no change or
the clinician and the patient believe is effective. an improvement. Twenty-two of 24 studies found that
In contrast to the patients’ self-reported symptoms, clicking improved after surgery; therefore, one can
the clinical findings seemed to advocate a reduction in guardedly advise patients of this. The results for crep-
clicking after surgery. The improvement in clicking itus were more varied, with some studies reporting an
might be related to repositioning of the condylar disc increase and others a decrease after surgery. Crepitus
complex especially during BSSO surgery for correc- is closely associated with pathology or resorption of
tion of Class II skeletal relationships.23 It must be the condylar head, and the exact influence of surgery
acknowledged that a reduction in clicking might not on this is unclear. The incidence of condylar resorp-
necessarily relate to recapturing the disc but, rather, tion, however, was about 7.5%.13
American Journal of Orthodontics and Dentofacial Orthopedics Al-Riyami, Cunningham, and Moles 626.e13
Volume 136, Number 5
Study estimate/
Study/method pooled estimate Lower Upper
1. Set criteria should be used for diagnosing and clas- 10. Athanasiou AE, Yücel-Eroğlu E. Short-term consequences of or-
sifying TMD that are valid, reproducible, and sim- thognathic surgery on stomatognathic function. Eur J Orthod
1994;16:491-9.
ple to carry out. 11. Panula K, Somppi M, Finne K, Oikarinen K. Effects of orthog-
2. Future research in TMD should adhere to an inter- nathic surgery on temporomandibular joint dysfunction. A con-
nationally recognized set of criteria and a universal trolled prospective 4-year follow-up study. Int J Oral Maxillofac
scale. Surg 2000;29:183-7.
3. More prospective longitudinal studies are needed 12. Pahkala R, Heino J. Effects of sagittal split ramus osteotomy on
temporomandibular disorders in seventy-two patients. Acta
with strict quality-assurance protocols to minimize Odontol Scand 2004;62:238-44.
bias, thus increasing their standing in the evidence- 13. Kallela I, Laine P, Suuronen R, Lindqvist C, Iizuka T. Assessment
based hierarchy. of material- and technique-related complications following sagit-
4. Research should focus on categorizing participants tal split osteotomies stabilized by biodegradable polylactide
homogenously to reduce the effects of confounding screws. Oral Surg Oral Med Oral Pathol Oral Radiol Endod
2005;99:4-10.
factors and enable adequate comparisons to be 14. Little S, Showfety K, Moshiri F, Jackson R, Moshiri F. Posttreat-
made between studies. ment evaluation of temporomandibular joint dysfunction after or-
thodontics and maxillary surgical impaction. Int J Adult Orthod
By heeding these recommendations, it should be Orthognath Surg 1986;1:225-30.
possible to conduct good-quality studies that are ade- 15. Athanasiou AE, Elefteriadis J, Dre E. Short-term functional alter-
quately homogenous to allow comparisons and enable ations in the stomatognathic system after orthodontic-surgical
statistical analyses, further strengthening conclusions management of skeletal vertical excess problems. Int J Adult
about TMD and orthognathic surgery. Orthod Orthognath Surg 1996;11:339-46.
16. Higgins JPT, Green S, editors. Cochrane handbook for systematic
We thank Professor Athanasios Athanasiou for pro- reviews of interventions. Version 5.0.0 (updated February 2008).
viding further invaluable information regarding his The Cochrane Collaboration; 2008. Available at: www.
cochrane-handbook.org. Accessed on October 28, 2008.
studies. 17. Deeks J, Higgins JPT, Altman D, editors. Analysing data and under-
taking meta-analyses. In: Higgins JPT, Green S, editors. Cochrane
handbook for systematic reviews of interventions. Version 5.0.0
(updated February 2008). The Cochrane Collaboration; 2008.
REFERENCES Available at: www.cochrane-handbook.org. Accessed on October
1. Borstlap W, Stoelinga P, Hoppenreijs T, van’t Hof M. Stabilisation 28, 2008.
of sagittal split advancement osteotomies with miniplates: a pro- 18. Westermark A, Shayeghi F, Thor A. Temporomandibular dys-
spective, multicentre study with two-year follow-up. Part III— function in 1,516 patients before and after orthognathic surgery.
condylar remodelling and resorption. Int J Oral Maxillofac Surg Int J Adult Orthod Orthognath Surg 2001;16:145-51.
2004;33:649-55. 19. De Clercq C, Neyt L, Mommaerts M, Abeloos J. Orthognathic
2. Luther F. Orthodontics and the temporomandibular joint: where surgery: patients’ subjective findings with focus on the temporo-
are we now? Part II. Functional occlusion, malocclusion, and mandibular joint. J Craniomaxillofac Surg 1998;26:29-34.
TMD. Angle Orthod 1998;68:305-18. 20. Aghabeigi B, Hiranaka D, Keith D, Kelly J, Crean S. Effect of or-
3. Wolford L, Reiche-Fischel O, Mehra P. Changes in temporoman- thognathic surgery on the temporomandibular joint in patients
dibular joint dysfunction after orthognathic surgery. J Oral with anterior open bite. Int J Adult Orthod Orthognath Surg
Maxillofac Surg 2003;61:655-60. 2001;16:153-60.
4. White C, Dolwick M. Prevalence and variance of temporoman- 21. Hackney F, Van Sickels J, Nummikoski P. Condylar displacement
dibular dysfunction in orthognathic surgery patients. Int J Adult and temporomandibular joint dysfunction following bilateral sag-
Orthod Orthognath Surg 1992;7:7-14. ittal split osteotomy and rigid fixation. J Oral Maxillofac Surg
5. O’Rourke K, Detsky A. Meta-analysis in medical research: srong 1989;47:223-7.
encouragement for higher quality in individual research efforts. J 22. Scott B, Clark G, Hatch J, van Sickels J, Rugh J. Comparing pro-
Clin Epidemiol 1989;42:1021-6. spective and retrospective evaluations of temporomandibular dis-
6. Huque MF. Experiences with meta-analysis in NDA submissions. orders after orthognathic surgery. J Am Dent Assoc 1997;128:
Proceedings of the Biopharmaceutical Section of the American 999-1003.
Statistical Association 1988;2:28-33. 23. Gaggl A, Schultes G, Santler G, Kärcher H, Simbrunner J. Clini-
7. Egger M, Davey Smith G, Altman DG, editors. Systematic re- cal and magnetic resonance findings in the temporomandibular
views in health care: meta-analysis in context. 2nd ed. London: joints of patients before and after orthognathic surgery. Br J
BMJ; 2001. Oral Maxillofac Surg 1999;37:41-5.
8. Helkimo M. Studies on function and dysfunction of the mastica- 24. Dervis E, Tuncer E. Long-term evaluations of temporomandibular
tory system. II. Index for anamnestic and clinical dysfunction and disorders in patients undergoing orthognathic surgery compared
occlusal state. Sven Tandlak Tidskr 1974;67:101-21. with a control group. Oral Surg Oral Med Oral Pathol Oral Radiol
9. Smith V, Williams B, Stapleford R. Rigid internal fixation and the Endod 2002;94:554-60.
effects on the temporomandibular joint and masticatory system: 25. Herbosa E, Rotskoff K, Ramos B, Ambrookian H. Condylar posi-
a prospective study. Am J Orthod Dentofacial Orthop 1992;102: tion in superior maxillary repositioning and its effect on the tem-
491-500. poromandibular joint. J Oral Maxillofac Surg 1990;48:690-6.
626.e16 Al-Riyami, Cunningham, and Moles American Journal of Orthodontics and Dentofacial Orthopedics
November 2009
26. Ueki K, Nakagawa K, Takatsuka S, Shimada M, Marukawa K, 36. Egermark I, Blomqvist J, Cromvik U, Isaksson S. Temporoman-
Takazakura D, et al. Temporomandibular joint morphology and dibular dysfunction in patients treated with orthodontics in com-
disc position in skeletal Class III patients. J Craniomaxillofac bination with orthognathic surgery. Eur J Orthod 2000;22:
Surg 2000;28:362-8. 537-44.
27. Rodrigues-Garcia R, Sakai S, Rugh J, Hatch J, Tiner B, van Sickels J, 37. Karabouta I, Martis C. The TMJ dysfunction syndrome before and
et al. Effects of major Class II occlusal corrections on temporoman- after sagittal split osteotomy of the rami. J Maxillofac Surg 1985;
dibular signs and symptoms. J Orofac Pain 1998;12:185-92. 13:185-8.
28. Nemeth D, Rodrigues-Garcia R, Sakai S, Hatch J, Van Sickels J, 38. Upton L, Scott R, Hayward J. Major maxillomandibular malrela-
Bays R, et al. Bilateral sagittal split osteotomy and temporoman- tions and temporomandibular joint pain-dysfunction. J Prosthet
dibular disorders: rigid fixation versus wire fixation. Oral Surg Dent 1984;51:686-90.
Oral Med Oral Pathol Oral Radiol Endod 2000;89:29-34. 39. Turner J, Deyo R, Loeser J, Von Korff M, Fordyce WE. The im-
29. Azumi Y, Sugawara J, Takahashi I, Mitani H, Nagasaka H, portance of placebo effects in pain treatment and research.
Kawamura H. Positional and morphologic changes of the mandib- JAMA 1994;271:1609-14.
ular condyle after mandibular distraction osteogenesis in skeletal 40. Ueki K, Marukawa K, Nakagawa K, Yamamoto E. Condylar
Class II patients. World J Orthod 2004;5:32-9. and temporomandibular joint disc positions after mandibular
30. Borstlap W, Stoelinga P, Hoppenreijs T, van’t Hof M. Stabilisation osteotomy for prognathism. J Oral Maxillofac Surg 2002;60:
of sagittal split advancement osteotomies with miniplates: a pro- 1424-32.
spective, multicentre study with two-year follow-up. Part I. Clin- 41. Zimmer B, Schwestka R, Kubein-Meesenburg D. Changes in
ical parameters. Int J Oral Maxillofac Surg 2004;33:433-41. mandibular mobility after different procedures of orthognathic
31. Aoyama S, Kino K, Kobayashi J, Yoshimasu H, Amagasa T. Clin- surgery. Eur J Orthod 1992;14:188-97.
ical evaluation of the temporomandibular joint following orthog- 42. Schneider S, Witt E. The functional findings before and after
nathic surgery—multiple logistic regression analysis. J Med Dent a combined orthodontic and oral surgical treatment of Angle Class
Sci 2005;52:109-14. III patients. Fortschr Kieferorthop 1991;52:51-9.
32. Timmis D, Aragon S, Van Sickels J. Masticatory dysfunction with 43. Link J, Nickerson J Jr. Temporomandibular joint internal derange-
rigid and nonrigid osteosynthesis of sagittal split osteotomies. ments in an orthognathic surgery population. Int J Adult Orthod
Oral Surg Oral Med Oral Pathol 1986;62:119-23. Orthognath Surg 1992;7:161-9.
33. Athanasiou AE, Melsen B. Craniomandibular dysfunction follow- 44. Laskin D, Ryan W, Greene C. Incidence of temporomandibular
ing surgical correction of mandibular prognathism. Angle Orthod symptoms in patients with major skeletal malocclusions: a survey
1992;62:9-14. of oral and maxillofacial surgery training programs. Oral Surg
34. Cutbirth M, Van Sickels J, Thrash WJ. Condylar resorption after Oral Med Oral Pathol 1986;61:537-41.
bicortical screw fixation of mandibular advancement. J Oral Max- 45. Kahnberg E. TMJ complications associated with superior reposi-
illofac Surg 1998;56:178-82. tioning of the maxilla. J Cranio Pract 1988;6:312-5.
35. Zhou Y, Hägg U, Rabie A. Patient satisfaction following orthog- 46. Mavreas D, Athanasiou AE. Tomographic assessment of alter-
nathic surgical correction of skeletal Class III malocclusion. Int J ations of the temporomandibular joint after orthognathic surgery.
Adult Orthod Orthognath Surg 2001;16:99-107. Eur J Orthod 1992;14:3-15.