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Surgical-orthodontic treatment and patients’ functional and psychosocial well-being

Surgical-orthodontic treatment and patients’ functional and psychosocial well-being

American Journal of Orthodontics and Dentofacial Orthopedics, 2007-08-01, Volume 132, Issue 2, Pages 158-164, Copyright © 2007 American Association of Orthodontists

Introduction: Surgical-orthodontic treatment is a common treatment approach for adult patients with skeletal maxillomandibular discrepancy. Some patients report improvement in signs and symptoms of temporomandibular disorder (TMD) after surgery. Whether the correction of malocclusion is responsible for the improvement of TMD symptoms after orthognathic surgery is still controversial. The objectives of this prospective study were to evaluate subjective treatment outcomes in patients with bilateral sagittal split osteotomy (BSSO) and to find out whether signs and symptoms of TMD and changes in occlusion are related to patient satisfaction. Methods: Eighty-two patients (53 female, 29 male) with a mean age of 32 years (range, 16-53 years) treated with BSSO in the Oral and Maxillofacial Department at Kuopio University Hospital in Finland were examined; 64 had mandibular advancement, and 18 had mandibular setback. Occlusion and signs and symptoms of TMD were registered pre- and postoperatively. At the postoperative examination (mean, 1.8 years after BSSO), the patients were asked to fill out a questionnaire about the influence of treatment on their masticatory function and symptoms of TMD, as well as their satisfaction with the treatment outcome. Results: TMD symptoms were significantly reduced after treatment. Improvements were also reported in facial appearance (82%) and chewing ability (61%); also, facial (56%) and temporomandibular joint (40%) pain disappeared. However, in 12% of the patients, temporomandibular joint problems were worse after treatment. Most patients (73%) were very satisfied with the outcomes; no one expressed dissatisfaction. Multiple logistic regression analysis showed that subjects with improved mastication and self-confidence, and those without long-term neurosensory deficits, expressed high satisfaction with the treatment outcome. Patients with mandibular setback were more pleased with the outcome than those with mandibular advancement. Conclusions: Orthognathic patients generally experience functional and psychosocial benefits after surgical-orthodontic treatment. In addition to functional and morphological reasons, the psychosocial factors should be more emphasized when making the treatment decision and comparing the alternative treatment approaches.

Surgical-orthodontic treatment is a commonly used approach for adults with skeletal maxillomandibular discrepancy. In addition to improving occlusal function, it aims to produce more harmonious facial skeletal relationships. Generally, bilateral sagittal split ramus osteotomy (BSSO) of the mandible has been reported to have a favorable effect on temporomandibular disorders (TMD), although there is a risk that preoperatively asymptomatic patients can develop TMD. Our previous results showed that patients with signs of mainly myogenous origin got more relief from their dysfunction than those with mainly arthrogenous components of TMD. Whether the correction of malocclusion is responsible for the improvement of TMD symptoms after orthognathic surgery is still controversial.

Regarding patient satisfaction, Mihalik et al showed that properly selected patients for orthodontic camouflage treatment are equally satisfied with the outcome as those who have surgery. It was suggested that patients who perceive themselves as outside the normal range are more likely to prefer surgery and to be dissatisfied with orthodontic tooth movement alone, a determination that cannot be evaluated solely on physical records.

The quality of treatment outcome has become increasingly important in medical sciences in recent years, although there is little agreement on the definition of quality of life. It is also well known that patients’ ratings of outcome might not correlate with those of clinicians. Since surgical-orthodontic treatment is a long-lasting and costly process with well-recognized risks, there is a need to evaluate how satisfied patients are with treatment outcomes.

The aim of this study was to test the following hypotheses: (1) surgical-orthodontic treatment relieves the symptoms of TMD, mainly in patients with myogenic components of TMD; and (2) the patients who are the most satisfied with the treatment outcome are those whose TMD signs and symptoms are relieved most and whose occlusion improves greatly.

Material and methods

This prospective study included 82 consecutive orthognathic patients who had BSSO surgery between 1998 and 2004 in the Oral and Maxillofacial Department at Kuopio University Hospital in Finland. The mean age of the 53 women and the 29 men was 32 years (SD, 10.2; range, 16-53 years). Most, 64 patients, had mandibular advancements, and 18 had setbacks of the mandible. Model surgery simulating the degree of necessary mandibular movement was used to generate the occlusal splint for operative and postoperative use. Internal rigid fixation with bicortical screws was used for the osteosynthesis, and all patients had pre- and postoperative orthodontic treatment with fixed appliances. Patients undergoing additional simultaneous surgery (chin or maxilla osteotomies) and those who moved away during the orthodontic treatment were excluded from this study. The distribution of preoperative primary diagnoses is given in the Table I . The underlining skeletal deformity for the diagnosis was assessed on lateral cephalograms.

Table I
Distribution of subjects (n = 82) by primary clinical diagnosis
Diagnosis n %
Mandibular hypoplasia/retrognathia 52 63
Mandibular hyperplasia/prognathia 14 17
Mandibular asymmetry 1 1
Anterior open bite 4 5
Deepbite 8 10
Dentoalveolar malposition 3 4

The patients were treated by a senior orthodontist (R.P.), who also supervised the treatments performed by 3 dentists specializing in orthodontics. The recording methods were calibrated. Three senior oral and maxillofacial surgeons performed the operations. During the first appointment, the orthodontist interviewed the patient about subjective symptoms of TMD and motivation for seeking treatment. During this examination, occlusion and clinical signs of TMD were also registered, including alginate impressions for dental casts. After the postoperative orthodontic treatment and a retention period (mean, 1.8 years [SD 0.5] after BSSO), the patients were clinically reexamined, posttreatment alginate impressions were taken, and the patients were asked to fill out the questionnaire about the influence of the treatment on their masticatory function and symptoms of TMD, and their satisfaction with the treatment outcome ( Fig 1 ).

Fig 1

To evaluate the treatment outcome on TMD signs and symptoms, the pre- and postoperative recordings were compared. The degree of TMD was assessed by using the anamnestic and modified clinical dysfunction indexes of Helkimo. Category E, “pain on movement of the mandible,” was replaced by “frequency of headache” (never/rarely, 0; 2-3 times a week, 1; almost daily, 5), because few patients had pain on movement of the mandible. The anamnestic index (Ai) classifies patients into 3 groups depending on severity of the symptoms: Ai0, those with no symptoms of dysfunction in the masticatory system; AiI, those with mild symptoms of dysfunction (joint noises or a feeling of tiredness or stiffness of jaws); and AiII, those with severe symptoms such as pain in masticatory muscles or temporomandibular joint (TMJ), difficulties in opening the mouth, locking, or luxation of jaws.

The determination of the modified clinical dysfunction index and the results of the changes in the clinical TMD signs are described in detail elsewhere.

Furthermore, for the statistical analysis, the subjects were classified into 3 subgroups depending on disorder type based on the modified criteria described by the American Academy of Orofacial Pain. The TMD myo group comprised 24 patients with pain on palpation of at least 1 masticatory muscle and no TMJ tenderness and no radiological evidence of organic changes in the TMJs. The TMD arthro group was composed of 24 subjects with no palpatory tenderness of the muscles but pain on palpation of the TMJs or radiologic evidence of organic changes in the TMJs or clicking. Fifteen patients with signs both in muscles and TMJs were classified in the TMD combi group . Nineteen subjects had no signs of TMD. The morphology of each condyle was recorded on panoramic radiographs before treatment. Fisher exact tests were used to analyze the differences in patients’ satisfaction with outcome in those groups. The differences in the subjective dysfunction index between preoperative and postoperative examinations were tested with the Wilcoxon signed ranks test.

The improvement in the anatomical occlusion was assessed by comparing the dental casts with the peer assessment rating (PAR) index. It provides a measure of the occlusion, taking into account overjet, overbite, buccal occlusion, midlines, and maxillary and mandibular anterior alignment.

Multiple logistic regression analyses were used to estimate the association between patients’ satisfaction with treatment outcome (0, rather satisfied; 1, very satisfied) and the following variables: direction of the BSSO (1, mandibular advancement; 2, mandibular setback), change in chewing ability (1, improved; 2, no change; 3, worsened), change in TMJ problems (1, improved; 2, no change; 3, worsened), change in facial pain and headache (1, improved; 2, no change; 3, worsened), change in self-confidence (0, no change; 1, improved), and long-term (>6 months after surgery) neurosensory deficit (0, no; 1, yes). Changes in clinical and anamnestic dysfunction indexes and the PAR index were included in the models as continuous independent variables. The effects of age (in years) and sex (0, female; 1, male) were also considered. For all comparisons, P values ≤.05 were considered statistically significant.

The study was approved by the Ethics Committee of the Kuopio University Hospital.


In this study, the most common reasons for seeking surgical-orthodontic treatment were regular headache and facial pain (43%), problems with TMJs (30%), chewing difficulties (23%), and dissatisfaction with facial or dental appearance (11%); 44% of the subjects were recommended by professionals to have orthodontic/orthognathic treatment.

Nearly all patients (96%) answered that they had received enough information about the various treatment procedures before making the treatment decision. Thirty-seven percent of the subjects had experienced intense pain during orthodontic treatment, and 60% of them had intense pain of short duration after surgery. Almost half of the patients (48%) had sometimes used pain-killers for orthodontic pain. In addition, 73% of the participants had had subjectively some level of numbness in the lips or jaw after surgery, and, in 20%, this subjective feeling had persisted for more than 6 months.

There was a statistically significant change in anamnestic dysfunction index between pre- and postoperative examinations ( Table II ). Preoperatively, 54% of the patients had suffered from severe symptoms of dysfunction, whereas 34% were free from symptoms. At the follow-up visit (mean, 1.8 years [SD 0.5] after BSSO), those percentages were 28% and 56%, respectively.

Table II
Changes in preoperative and postoperative anamnestic dysfunction index in 82 patients who underwent BSSO
Preoperative index (n) Postoperative index
Ai0 n AiI n AiII n P
Ai0 (28) 21 2 5
AiI (10) 5 1 4
AiII (44) 20 10 14
Total (82) 46 13 23

Wilcoxon signed rank test.

Mastication ability improved in 61% of the patients, but 6% thought that their chewing ability was decreased after treatment ( Fig 2 ). Forty percent of those with problems in the TMJs and 56% with facial pain and headache preoperatively experienced improvement after the treatment. In 10 patients, subjective TMJ problems worsened after surgery, but only 1 reported more facial pain after surgery. No change in TMJ pain and headache was noticed in 20% and 12% of the participants, respectively. Sixty-seven of the patients (82%) thought that their facial appearance had clearly improved, and no one felt that it had worsened after treatment. Only 2 patients experienced difficulties in adjusting to their changed appearance. Furthermore, 37 subjects (45%), mainly women, said that the treatment had had a positive effect on their self-confidence. The change in self-confidence between sexes was statistically significant ( P = .040).

Changes in facial appearance, chewing ability, facial pain or headache, and TJM pain.
Fig 2
Changes in facial appearance, chewing ability, facial pain or headache, and TJM pain.

Most patients (73%) were very satisfied, 27% were rather satisfied, and no one expressed dissatisfaction with the treatment outcome. Almost one third (29%) of the patients considered the treatment results to be better than expected, and 65% replied that they were as good as expected. Five patients (6%) thought that their expectations had not been fulfilled. Altogether, 84% of the patients would be willing to undergo the same surgical-orthodontic treatment in the same situation again, 2% would have said no, and 14% were unsure of their answer.

Multiple logistic regression analysis ( Table III ) showed that changes in chewing ability and self-confidence were significantly related to high satisfaction with the treatment outcome. In addition, those with mandibular setback seemed to be more satisfied with the treatment outcome than those with mandibular advancement. The degree of surgical advancement or setback was not correlated with patient satisfaction ( P = .974). Also, those without a long-term neurosensory deficit were more likely to be pleased with the treatment. Neither age, sex, nor the changes in dysfunction indexes or PAR index were associated with high satisfaction in the logistic regression analysis, although there was a significant positive correlation between patient satisfaction and the reduction in PAR score and changes in subjective TMJ and facial pain (Pearson correlation test, P = .042, P = .023, and P = .010, respectively). The PAR index dropped from a mean of 16.8 before surgical-orthodontic treatment to 4.2 about 2 years postoperatively. Furthermore, patients with signs of mainly arthrogenous components of TMD were significantly more pleased with the treatment outcome than those in the other groups ( Table IV ).

Table III
Relationship between satisfaction (0, rather satisfied; 1, very satisfied) with treatment outcome and independent variables by logistic regression analysis (only statistically significant variables are listed)
Independent variable Regression coefficient P
Change in chewing ability −1.04 .046
Change in self-confidence 1.76 .018
BSSO 2.38 .048
Long-term numbness in lips or jaw −1.62 .034

Table IV
Number of patients who underwent BSSO reporting high satisfaction with treatment outcome
Group n (%) P
Myo 15 (63) .130
Arthro 21 (88) .049
Combi 9 (60) .170

Fisher exact test (very satisfied vs rather satisfied).


Patient satisfaction is an important goal in health care, but it is difficult to define satisfaction. It involves physical, psychological, and social aspects, as well as factors such as realistic or unrealistic expectations, external or hidden motives, information, and communication between the patient and the professional. It has been shown that patients who expect to have major problems after surgery report more postsurgical problems than those who expect minimal problems. Furthermore, subjects who believed that they were given too little information about the procedures tended to be dissatisfied with the treatment outcome. Sociocultural differences in satisfaction and motives for treatment are also well recognized. Rivera et al showed that Mexican American patients indicated more psychosocial reasons than European Americans for seeking surgical-orthodontic treatment. In Japanese patients, the response from relatives and friends was an important factor influencing satisfaction with the treatment outcome. In addition, it was reported that, although patients usually experience a decline in self-esteem and body image up to 9 months after surgery, by 24 months postsurgery, the overall body image improved beyond the level at presurgery. It seems that improvement in facial features has a beneficial influence on patients’ self-esteem and also on their social lives.

As in many other studies in this field, we also found that the psychosocial benefits of orthognathic treatment could not be evaluated objectively because the measures of the baseline psychological status were missing. However, it seems that short-term fluctuation in factors affecting satisfaction was avoided because the questionnaire was filled out almost 2 years postoperatively. Regarding long-term effects in health-related quality of life and psychosocial functions, Motegi et al suggested that the gained improvements are stable between 2 and 5 years after BSSO.

To evaluate the effectiveness of orthognathic treatment on TMD and occlusion, we used the Helkimo and PAR indexes, which made it possible to determine the severity of problems before and after treatment. With treatment, both the severity of dysfunction signs and symptoms clearly decreased and the occlusion improved markedly. Because there has been criticism of the Helkimo index in that it does not distinguish between joint and muscle dysfunction, we modified it to determine which patients benefited most from the treatment. Our previous results showed that patients with mainly myogenous origin got more relief from their dysfunction signs than patients with mainly arthrogenous components of TMD, underlining the importance of harmonious occlusion on physiological fine oral motor activities. However, in this study, patients in the arthro group were more pleased with the treatment outcome than those in the myo and combi groups. This might indicate that the preoperative TMD signs and symptoms in subjects with arthrogenous problems had been more disturbing than in the other groups, and treatment made those signs more tolerable. On the other hand, it can be speculated that those patients’ emotional tone had changed because of improved self-image, or they focused on other aspects of their lives, regardless of the functional outcome.

As one would expect, orthognathic treatment improved chewing ability in most subjects. This indicates that harmonious occlusion improves tooth interdigitation and makes the orofacial functions more physiological. However, 5 patients reported that their mastication had worsened after treatment. It is generally known that shortly after surgery the bite force and the occlusal contact area are lower than those of healthy subjects. Through postoperative orthodontics and adaptation to the new occlusion, normal values are approached in 1 to 3 years. Most probably because of worsened adaptation with age, Ostler and Kiyak recommended that, especially in older patients, clinicians should be more careful in preparing patients for possible masticatory problems postoperatively. Further analyses of the 5 patients with subjectively reduced chewing ability showed that, in 2, TMJ pain reduced masticatory capacity, and, in 3 (with several missing teeth), mandibular advancement had decreased the number of occluding teeth posteriorly. This underlines the importance of replacing missing teeth with prosthetics postoperatively.

Multiple logistic regression analyses showed that those with mandibular setback were more likely to be satisfied with the treatment outcome than those with mandibular advancement. It was found that normalization of the sagittal relationship from Class III to Class I reduces dysfunction symptoms, and orthognathic treatment outcome concerning TMD is less favorable in patients with mandibular retrognathia than with mandibular prognathia. On the other hand, a prognathic mandible is esthetically considered to be more disturbing than a retrognathic mandible, since patients with mandibular deficiency can “improve” their facial appearance by positioning the jaw forward.

Almost half of the patients, mainly women, reported that surgical-orthodontic treatment had had a positive effect on their self-confidence. This underlines the importance of dental and facial attractiveness and harmonious occlusion on self-image and social adjustment. After orthognathic treatment, the women reportedly wore more makeup, were no longer afraid to smile, and felt more confident. The men, on the other hand, reported more functional considerations: “I can now enjoy good food and don’t have to avoid eating among other people.” Another usual comment was that regular headaches had disappeared after treatment. These results are parallel to previous studies. As reported by Mihalik et al, patients with orthodontic camouflage treatment are as satisfied as patients with surgical-orthodontic treatment. However, patients who had their mandibles advanced were significantly more positive about their dentofacial images. These results suggest that, when alternative treatment approaches are possible, we as professionals should be more sensitive in listening to the patients’ main motives for seeking treatment and their expectations about treatment outcome.

In accordance with the report of Finlay et al, our results showed that long-term numbness of lips or jaw is an important factor that has an effect on a patient’s overall satisfaction. Our finding that 20% of the patients had subjectively some postoperative numbness of the lips or jaw for more than 6 months is within the range (8%-49%) of other studies. In our study, no long-term objective testing of neurosensory deficit was done, but, as reported in other studies, after BSSO there still seems to be a good chance for long-term (6 months to 2 years) neurosensory recovery. However, despite this deficit, most orthognathic patients do not find that partial sensory disturbance bothered them in their everyday life. In general, it is important to tell patients about the risk of neurosensory deficit before they make the decision about the treatment procedure.

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