Int. J. Oral Maxillofac. Surg. 2000; 29: 183–187 Copyright C Munksgaard 2000 Printed in Denmark . All rights reserved ISSN 0901-5027 Kari Panula1, Matti Somppi2, Kaj Finne1,Kyo¨ sti Oikarinen3 Effects of orthognathic surgery 1 Department of Oral and Maxillofacial Surgery, Vaasa Central Hospital; 2Department of Oral and Maxillofacial Surgery, Seina¨joki on temporomandibular joint Central Hospital; 3Department of Oral and Maxillofacial Surgery, University of Oulu, dysfunction Finland A controlled prospective 4-year follow-up study K. Panula, M. Somppi, K. Finne, K. Oikarinen: Effects of orthognathic surgery on temporomandibular joint dysfunction. A controlled prospective 4-year follow-up study. Int. J. Oral Maxillofac. Surg. 2000; 29: 183–187. C Munksgaard, 2000 Abstract. A prospective follow-up study was performed to examine the influence of contemporary orthognathic treatment on signs and symptoms of TMJ dysfunction. Sixty consecutive patients were examined once preoperatively and twice postoperatively, and Helkimo’s Anamnestic and Dysfunction Indices (Ai and Di) were determined. The prevalence of headache was also assessed. The average follow-up was 4 years from the initial examination. A group of 20 patients with a similar type and grade of dentofacial deformity, who did not wish to have surgery or other occlusal therapy, served as a control group. The majority (73.3%) of the patients had signs and symptoms of TMJ dysfunction (TMD) in the initial phase. At final examination the prevalence of TMD had been reduced to 60% (P½0.013). There was a dramatic improvement in headache: initially 38 (63%) patients reported that they suffered from headache, but at the final visit only 15 (25%) did so. It is concluded that functional status can be significantly improved and pain levels reduced with orthognathic treatment. The Key words: orthognathic treatment; TMJ dysfunction; dentofacial deformity; headache. risk for new TMD is extremely low. No association, however, could be shown between TMD and the specific type or magnitude of dentofacial deformity. Accepted for publication 16 November 1999 Apart from improvement in appear- On the other hand, some authors have tients with similar malocclusions who ance, an important goal of orthogna- not found any significant improvement had refused surgery, was used as a con- thic treatment is to improve masticatory in TMD or any particular relation be- trol group. function. It is, however, somewhat con- tween TMD and the specific type of troversial as to whether this goal is al- dentofacial deformity2,13,21,22,27. The ways achieved1,13,19–21,28. Even though growing demand to cut costs of health Material and methods many studies report reduction in TMJ care forces clinicians to provide evi- The study group consisted of 60 consecutive dysfunction (TMD) symptoms after dence-based and cost-effective treat- patients (49 women, 11 men) with a mean age orthognathic surgery3,4,10–12,14,16,18,29, ment. of 33.2 years (median 32.7 years, range 16– most studies have some serious flaws in It has been mentioned that retrospec- 56 years) referred for consultation and treat- that small patient samples are used14,18, tive studies tend to overestimate treat- ment to the Departments of Oral and Max- whereas others are retrospective in na- ment benefits25. The aim of this study illofacial Surgery of the Central Hospitals of Vaasa or Seina¨joki. All of the patients had ture3,4,14,29. In some studies periods of was to analyse prospectively the effects preoperative orthodontics and they were op- intermaxillary fixation (IMF) have been of orthognathic surgery with contem- erated on in Vaasa between 1993 and 1995, 11,12,14,18 used , while in others the fol- porary rigid fixation methods on TMD. using rigid internal fixation without IMF. low-up seemed rather short3,4,11,18 or In order to facilitate a comparison with Fixation was performed with AO-position the studies have been case reports10,16. a non-treatment group, a group of pa- screws in the mandible and miniplates in the 184 Panula et al. maxilla. There were initially 65 patients, but examined on panoramic tomographies at the Data analysis was not performed until the 5 were deleted from the study; two patients first and latest examination in the study last patient had been examined for the last were treated with orthodontics only, one group. In order to assess any possible associ- time to prevent bias from the examiner’s could not be reached for final examination, ation of mandibular plane angle to the sever- awareness of any trends in the basic data. one was found to suffer from a neuromuscu- ity of TMD, the SN-MeGo angle was meas- lar disorder and one had a severe psycho- ured on the lateral cephalograms preopera- logical disorder. tively as described by DC et al.3, K- Results A group of 20 patients (16 women, 4 men) et al.12 and S et al. 23, who There were no significant differences be- seeking treatment for similar deformities but compared the measurements to a value of who did not wish to have treatment after the 32æ. tween the study and control groups in information was given at the first visit, The frequency of headache was assessed age, gender distribution and type or served as a control group. The mean age in using the following categories: (1) one or two magnitude of the dentofacial deformity. this group was 31.5 years (median 33.0 years, times a month, (2) one or two times a week, Signs and symptoms of TMD were range 15–44 years). (3) more than one or two times a week, (4) frequently seen throughout the follow- The patients in the study group were as- ‘‘migraine type’’ (symptoms like in migraine up, as shown in Table 3. Forty-four pa- sessed for signs and symptoms of temporo- but no diagnosis made by neurologist). Some tients (73.3%) had at least one sign or mandibular dysfunction three times: (1) be- patients did not have headache at all or less symptom of TMD preoperatively and fore orthodontic treatment (approximately than once a month. 36 after 4-year follow-up (60%), which 19 months preoperatively, range 7–32 The distributions of diagnosis and oper- months), (2) approximately 12 months post- ations performed are shown in Tables 1 and represented a significant reduction (P½ operatively (range 9–16 months), when active 2. The majority of patients in both study and 0.013). Muscle palpation tenderness orthodontic treatment was finished, (3) ap- control groups had mandibular hypoplasia, and headache were also reduced sig- proximately 29 months postoperatively 32 had class II division 1 and 16 class II divi- nificantly (Table 3). The control group (range 20–44 months). The mean total fol- sion 2 malocclusion in the study group, while was initially almost identical: 75% (15) low-up time was thus four years on average. 15 had class II division 1 and 4 division 2 had some sign or symptom, but in con- Eight of the patients had previously had oc- malocclusion in the control group. Twelve trast to the study group, this score in- clusal splint therapy and four had had oc- study patients and four control patients had creased during the follow-up to 85% clusal grinding. an anterior open bite. (17). Four (6.7%) patients who had no The control group was examined twice: (1) Statistical analysis was performed using at the first visit, and (2) approximately 52 the Wilcoxon matched pairs signed-ranks TMD preoperatively, developed signs months later (range 33–70 months). test to test the difference between measure- and symptoms of TMD postopera- Each examination included a written an- ments (two-tailed P-values in results) and by tively. One patient in the study group amnestic questionnaire and both a clinical Spearman rank correlation (rs). and one in the control group underwent and a radiological examination, but because some subjects in the control group refused radiography at the final visit, no radiological Table 1. Distribution of preoperative diagnosis among 60 patients in study group and 20 comparison could be made in the control control patients group. In the questionnaire the patient answered Study group Control group yes or no to questions concerning joint Diagnosis (n½60) (n½20) noises, locking, joint pain, pain in the facial Mandibular hypoplasia 40 16 musculature, stiffness/difficulties in mouth Mandibular hypoplasia, anterior open bite 5 3 opening, clenching of the teeth and ear pain, Mandibular hyperplasia 5 and reported the frequency of headache. Mandibular hyperplasia, anterior open bite 4 1 The clinical examination was performed Maxillary hypoplasia 1 by one of the two researchers (KP, MS) and Maxillary hypoplasia, anterior open bite 1 consisted of occlusal classification according Maxillary hyperplasia (VME), anterior open bite 2 to Angle and assessment of overjet, overbite, Maxillary and mandibular hypoplasia 2 maximal mouth opening, deviation at mouth opening, lateral and protrusive movements, VME½vertical maxillary excess. horizontal and lateral glide between retruded contact position (RCP) and intercuspal posi- tion (ICP), mediotrusive and laterotrusive in- Table 2. Number of operations performed for 60 patients terferences, number of occluding pairs of BSSO/advancement 35 teeth, pain when moving the jaw, palpation BSSO/set-back 2 and auscultation of the joints and palpation BSSO/advancement Genioplasty 5 of the masticatory muscles. The underlying ¹ LF I 3 skeletal deformity was assessed on lateral ce- Bimaxillary 15 phalograms. -LF I adv. with BSSO/adv. 1 The basic data from the questionnaire and -LF I adv. with BSSO/set-back 3 clinical examination were calculated and -LF I adv. with mandibular anterior segment 1 classified according to H’s 8 Anamnes- -LF I intrusion with BSSO/adv. (one with GP) 5 tic Index (Ai) (graded on a scale of Ai0½no -LF I intrusion with BSSO/set-back 1 subjective symptoms, AiI½mild subjective -LF I with segmentalization with BSSO/adv.