Temporomandibular joint and psychosocial evaluation of patients after orthognathic surgery: A preliminary study

PurposeThe purpose of this study was to evaluate the psychological and psychosocial status of patients prior to and after orthognathic surgery.Materials and methodsTwenty-two patients (13 males and 9 females) who underwent orthognathic surgery were examined in this study. The bilateral sagittal split ramus osteotomy (BSSRO) group included 10 patients, and the Le Fort I osteotomy and BSSRO group included 12 patients. We continued RDC/TMD Axis II research for 12 patients who had preoperative temporomandibular joint disorder (TMD). The RDC/TMD Axis II charts were recorded preoperatively and 6 months after surgery. The Wilcoxon signed rank test was used for statistical analysis.ResultsOverall, there was no significant difference between the preoperative and 6-month postoperative depression indices. The non-specific physical symptoms score (NPS) with pain score decreased significantly (p < 0.05), but the NPS without pain score decreased insignificantly. In terms of the graded pain score for the preoperative group, 75.0% of the patients were in the low disability group, whereas 25.0% were in the high disability group. In contrast, patients in the postoperative group only fell into the low disability group (p < 0.05).ConclusionThe RDC/TMD Axis II was developed to diagnose TMD, but we believe the RDC/TMD Axis II can help to establish postoperative treatment plans by evaluating a patient's psychological and psychosocial state.     

Axis II psychosocial findings predict effectiveness of TMJ hyaluronic acid injections

The objective was to investigate the correlation between levels of depression, somatization, and pain-related impairment, as assessed by the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMDs) axis II, and the treatment outcome of a cycle of five weekly injections of hyaluronic acid immediately following arthrocentesis. 57 consecutive patients with a diagnosis of temporomandibular joint (TMJ) osteoarthritis according to the RDC/TMD underwent the treatment protocol and a follow-up assessment at 6 months. Axis II findings were assessed as potential predictors of improvement in visual analogue scale (VAS) values at the end of the observation period with respect to baseline. The percentage of VAS improvement at the end of treatment was inversely related to all the psychosocial variables. The best fitting model identified pain-related impairment (p < 0.001) and disability points (p < 0.001) as the most significant predictors of VAS changes. The percentage of variance in the outcome variable explained by the significant predictors was high (R² 70.5%). All the RDC/TMD axis II psychosocial scores (depression, somatization, and pain-related impairment levels) were inversely correlated with therapeutic outcome. The clinical relevance of these findings is important, since psychosocial diagnosis may be even more important than physical evaluation in terms of prognostic impact.     

Correlation of somatization,depression, and chronic pain with clinical findings of the temporomandibular disorders in asymptomatic women

ABSTRACT

Objective: The aim of this study was to correlate degree of depression, somatization, and chronic pain in asymptomatic women with clinical findings, using Research Diagnostic Criteria/Temporomandibular disorders (RDC/TMD).

Methods: A total of 200 female participants, ages 18–65, filled out a standard RDC/TMD axis II form for the assessment of chronic pain, disability, depression, and non-specific physical symptoms and underwent clinical examination of the temporomandibular joint. Correlation of clinical findings (axis I) and axis II assessment was performed using Spearman’s correlation test, with significance set at p < 0.05.

Results: There was a significant correlation between depression scores (p < 0.04), chronic pain (p < 0.001), and non-specific physical symptoms without questions about pain (p = 0.008).

Discussion: The highest scores on the Graded Chronic Pain Scale were observed in patients with arthralgia, while patients with myofascial pain scored higher on depression and somatization tests.     

Depression and somatization in patients with temporomandibular disorders

STATEMENT OF PROBLEM: Psychological and behavioral traits may be important for the diagnosis and management of orofacial pain. PURPOSE: This study compared the levels of depression and somatization in patients in single and multiple research diagnostic criteria for temporomandibular disorders (RDC/TMD) diagnostic groups. MATERIAL AND METHODS: The RDC/TMD was established to allow standardization and replication of research into the most common forms of muscle- and joint-related research and is divided into 2 axes: axis I, clinical TMD, and axis II, pain-related disability and psychological status. One hundred seventeen patients (28 male and 89 female; mean age, 33.3 +/- 10.3 years) with RDC/TMD-defined clinical TMD were selected. The RDC/TMD history questionnaire and examination forms were input directly into computers with the use of a software program developed at the National University of Singapore (NUS TMDv1.1 software). Axis I and II variables were generated online and automatically archived for statistical analysis. Patients were subsequently classified into 7 groups based on the presence of the various RDC/TMD axis I diagnostic groups: group A, myofascial pain only (group I); group B, disk displacement only (group II); group C, other joint conditions such as arthralgia, osteoarthritis, and osteoarthrosis only (group III); group D, myofascial pain and disk displacement (groups I and II); group E, myofascial pain and other joint conditions (groups I and III); group F, disk displacement and other joint conditions (groups II and III); and group G, myofascial pain, disk displacement, and other joint conditions (groups I, II, and III). Differences in mean Symptom Checklist-90 scores between groups were compared by analysis of variance/Scheffé tests to contrast depression and somatization levels between the various axis I diagnostic groups (alpha=.05). RESULTS: The frequencies of the different groups were as follows: group A, 26.5%; group B, 29.9%; group C, 12.8%; group D, 6.0%; group E, 13.7%; group F, 4.3%; and group G, 6.8%. Approximately 39% of patients were clinically depressed, and 55% had moderate to severe somatization. Differences in mean depression and somatization with pain item scores were significant between groups (P<.05). CONCLUSION: Within the limitations of this study, patients diagnosed with myofascial pain and other joint conditions (group E) had significantly higher levels of depression (P=.03) and somatization (P=.03) than patients diagnosed with only disk displacements (group B).     

TMD before and after correction of dentofacial deformities by orthodontic and orthognathic treatment

The aims of the study were to investigate the alteration of temporomandibular disorders (TMD) after correction of dentofacial deformities by orthodontic treatment in conjunction with orthognathic surgery; and to compare the frequency of TMD in patients with dentofacial deformities with an age and gender matched control group. TMD were evaluated in 121 consecutive patients (treatment group), referred for orthognathic surgery, by a questionnaire and a clinical examination. 18 months after treatment, 81% of the patients completed a follow-up examination. The control group comprised 56 age and gender matched subjects, of whom 68% presented for follow-up examination. TMD were diagnosed according to research diagnostic criteria for TMD. At baseline examination, the treatment group had a higher frequency of myofascial pain (P = .035) and arthralgia (P = .040) than the control group. At follow-up, the frequencies of myofascial pain, arthralgia and disc displacement had decreased in the treatment group (P = .050, P = .004, P = .041, respectively). The frequency of TMD was comparable in the two groups at follow-up. Patients with dentofacial deformities, corrected by orthodontic treatment in conjunction with orthognathic surgery, seem to have a positive treatment outcome in respect of TMD pain.     

Psychosocial impairment in temporomandibular disorders patients. RDC/TMD axis II findings from a multicentre study

Objectives

The relationship between the rate of chronic pain-related disability and depression and somatization levels as well as the influence of pain duration on Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) axis II findings were assessed in a three centre investigation.

Methods

The study sample (N = 1149; F:M 4.1:1, m.a. 38.6 years) consisted of patients seeking for TMD treatment and undergoing RDC/TMD axis II psychosocial assessment to be rated in chronic pain-related disability (Graded Chronic Pain Scale, GCPS), depression (Symptoms Checklist-90[SCL-90] scale for depression, DEP) and somatization levels (SCL-90 scale for non-specific physical symptoms, SOM). The null hypotheses to be tested were that (1) no correlation existed between GCPS categories and DEP and SOM scores, and (2) no differences emerged between patients with pain from more or less than 6 months as for the prevalence of the different degrees of pain-related impairment, depression, and somatization.

Results

In the overall sample, the prevalence of high pain-related disability (GCPS grades III or IV), severe depression and somatization was 16.9%, 21.4%, and 28.5%, respectively. A correlation was shown between GCPS and both DEP and SOM categories (Spearman's correlation test, p < 0.001). A significant association between pain lasting from more than 6 months and high GCPS scores was shown (χ², p < 0.001), while no association was found between DEP and SOM scores and pain duration in the overall sample (χ², p = 0.742 and p = 0.364, respectively).

Conclusions

Pain-related disability was found to be strongly related with depression and somatization levels as well as associated with pain duration. Depression and somatization scores were not associated with pain duration.     

Dental malocclusion is not related to temporomandibular joint clicking: a logistic regression analysis in a patient population

Objectives:To assess the association of several dental malocclusion features with temporomandibular joint (TMJ) click sounds in a population of temporomandibular disorder (TMD) patients.Materials and Methods:Four hundred forty-two TMD patients (72% female; 32.2 ± 5.7 years, range 25–44 years) were divided into a TMJ clicking and a no-TMJ clicking group, based on the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) assessment. Seven occlusal features were recorded for each patient: (1) posterior crossbite, (2) overbite, (3) open bite, (4) overjet, (5) mediotrusive and (6) laterotrusive interferences and (7) retruded contact position to maximum intercuspation (RCP-MI) slide length. A logistic regression model was created to estimate the association of occlusal features with TMJ clicking.Results:The difference between the groups as for the prevalence of the various occlusal features was generally not statistically significant, with minor exceptions. Mediotrusive interferences (P  =  .015) and RCP-MI slide ≥2 mm (P  =  .001) were the two occlusal features that were associated with the probability of having TMJ clicking, even if the adjusted odds ratios for TMJ clicking were low for both variables (1.63 and 1.89, respectively). Moreover, the amount of variance in the prevalence of TMJ clicking that was predicted by the final model was as low as 4.5% (R²  =  0.045).Conclusions:Findings from the present investigation suggested that in a population of TMD patients, the contribution of dental malocclusion features to predict TMJ click sounds is minimal with no clinical relevance.     

Evaluation of recovery in lip closing pressure and occlusal force and contact area after orthognathic surgery

PurposeThe purpose of this study was to evaluate the relationship between lip closing force, occlusal contact area and occlusal force after orthognathic surgery in skeletal Class III patients.Subjects and methodsThe subjects consisted of 54 patients (28 female and 26 male) diagnosed with mandibular prognathism who underwent sagittal split ramus osteotomy with and without Le Fort I osteotomy. Maximum and minimum lip closing forces, occlusal contact area and occlusal force were measured pre-operatively, 6 months and 1 year post-operative.ResultsMaximum and minimum lip closing forces, occlusal contact area and occlusal force increased with time after surgery, however a significant increase was not found in the occlusal contact area in women. In increased ratio (6 months/pre-operative and 1 year/pre-operative), the maximum lip closing force was significantly correlated with the occlusal contact area (P < 0.0001).ConclusionsThis study suggested that orthognathic surgery could improve the occlusal force, contact area and lip closing force, and an increase ratio in maximum lip closing force was associated with an increased ratio in occlusal contact area.     

Influence of different surgical concepts for moderate skeletal class II and III treatment on the nasopharyngeal airway space

PurposeThis study aimed to compare the effects of different orthognathic and camouflage treatments for correcting moderate skeletal class II and III malocclusions on the pharyngeal airway space (PAS).Materials and methodsLateral cephalograms of 89 patients with moderate skeletal class II and III malocclusion (WITS up to 7 mm, −7 mm respectively) were evaluated before and after treatment. PAS was divided into 6 levels (P1: nasopharynx, P2-4: oropharynx, P5-6: laryngopharynx), and 7 groups were formed depending on the type of treatment: 1) class II, mandibular advancement; 2) class II, maxillary setback/mandibular advancement; 3) class II, upper premolar extraction; 4) class III, mandibular setback; 5) class III, maxillary advancement; 6) class III, maxillary advancement/mandibular setback; and 7) class III, lower premolar extraction.ResultsSignificant changes occurred only in patients with class II malocclusion (groups 1 and 2) before and after surgery in the nasopharyngeal and oropharyngeal space. Furthermore, significant differences between the patients with class II malocclusion were found when compared to the premolar extraction group: group 1 vs. group 3 (P3: −1.31 mm (SD 1.74 mm) vs. 0.89 mm (SD 1.79 mm); P4: −0.72 mm (SD 2.82 mm) vs. 1.42 mm (SD 2.16 mm); P ≤ 0.05), group 2 vs. group 3 (P2: 0.35 mm (SD 1.96 mm) vs. 2.28 mm (SD 1.88 mm), P3: −1.31 mm (SD 1.74 mm) vs. 0.35 mm (SD 1.96 mm), P4: −0.72 mm (SD 2.82 mm) vs. 2.84 mm (SD 2.16 mm), P ≤ 0.05).ConclusionsOrthognathic surgery in patients with moderate skeletal class II and III malocclusion seems to affect PAS only slightly. Premolar extractions for compensation (camouflage treatment) can result in a reduction of the oropharynx airway space in both types of skeletal malocclusions. Therefore, in borderline patients with presence of OSAS, orthognathic surgery should be considered.     

Diagnostic sub-types, psychological distress and psychosocial dysfunction in southern Chinese people with temporomandibular disorders

Summary  The study aimed to assess the distribution of temporomandibular disorders (TMD) sub-types, psychological distress and psychosocial dysfunction in southern Chinese people seeking treatment for TMD using Research Diagnostic Criteria for TMD (RDC/TMD) and investigate potential cross-cultural differences in sub-type prevalence and psychosocial impact. Eighty-seven consecutive patients (77 females; 10 males) with a mean age of 39·3 years (s.d. 12·8) newly referred to the specialist TMD clinic at the Prince Philip Dental Hospital, Hong Kong over a 20-month period took part in the study. RDC/TMD history questionnaire and clinical assessment data were used to derive Axis I and II findings. Group I muscle disorders were the most common and found in 57·5% of patients. Group II (disc displacement) disorders were found in 42·5% and 47·1% of the right and left temporomandibular joints (TMJ) respectively. Group III disorders (arthralgia/arthrosis/arthritis) were revealed in 19·5% and 23·0% of right and left TMJ's respectively. In the Axis II assessment, 42·5% of patients had moderate/severe depression scores, 59·7% had moderate/severe somatization scores and based on graded chronic pain scores 15·0% had psychosocial dysfunction (grade III and IV). While acknowledging the small sample size, the distribution of RDC/TMD Axis I and II diagnoses was fairly similar in Chinese TMD patients compared with Western and other Asian patient groups. However, in Chinese patients, myofascial pain with limited jaw opening and TMJ disc displacement with reduction were more common and a significant number experienced psychological distress and psychosocial dysfunction. The findings have implications for the management of TMD in Chinese people.     

Variation between natural head orientation and Frankfort horizontal planes in orthognathic surgery patients: 187 consecutive cases

The purpose of this study was to assess the relationship between the Frankfort horizontal (FH) and natural head orientation (NHO), their correlation between patients’ malocclusion, and the impact of counterclockwise rotation (CCW) on the FH-NHO angle variation after orthognathic surgery. An evaluation of 187 consecutive patients was performed at the Maxillofacial Institute (Teknon Medical Center, Barcelona). FH-NHO° was measured pre- and postoperatively at 1 and 12 months, after three-dimensional (3D) superimposition using a software (Dolphin®). Patients were classified as follows: 3.2%, 48.7% and 48.1%, class I, II and III, respectively. Baseline FH-NHO° was significantly positive for patients with dentofacial deformities (2.73° ± 4.19 (2.12–3.33°, P < 0.001). The impact of orthognathic surgery in FH-NHO° was greater in class II when compared with class III patients, with a variation of 2.04° ± 4.79 (P < 0.001) and −1.20° ± 3.03 (P < 0.001), respectively. FH-NHO° increased when CCW rotational movements were performed (P = 0.006). The results of this study suggest that pre- and postoperative NHO differs from FH in orthognathic patients. The angle between FH and NHO is significantly larger in class III than in class II patients at baseline, which converges after orthognathic surgery when CCW rotation is performed. Therefore, NHO should be used as the real horizontal plane when planning for orthognathic surgery.     

The prevalence of myofascial pain and its association with occlusal factors in a threshold country non-patient population

The objective of the study is to assess the prevalence of myofascial pain in a threshold country and to isolate occlusal risk factors. One hundred and seventy-one randomized selected women were examined by a trained examiner in accordance with the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) examination procedure. Subscales of the SCL 90-R, graded chronic pain status, and anamnestic questionnaires were also used. Logistic regression was performed to compute the odds ratios for six common occlusal features with regard to the presence of myofascial pain, in accordance with the RDC/TMD criteria. Fifteen subjects (15 / 151 = 9.93%) suffered from myofascial pain. Results from logistic regression analysis showed that non-occlusion (posterior teeth, at least one side) and open bite increased the risk of myofascial pain. The prevalence of myofascial pain in this study is comparable with that in another study, in a highly industrialized environment, in which the RDC/TMD was used. The role of occlusion in a non-patient population seems to be restricted to serious alterations of normality. This article presents the prevalence of myofascial pain and its association with occlusal factors. This issue will help the clinicians to assess the influence of occlusion in myofascial pain patients and to send the patient to the appropriate specialist.     

Prevalence and characteristics of systemic conditions in patients undergoing orthognathic surgery: a retrospective study

The aim of this study was to investigate the prevalence and characteristics of systemic conditions in patients undergoing orthognathic surgery at a tertiary centre. Ninety of the 838 patients undergoing orthognathic surgery between 2013 and 2019 had a systemic condition (prevalence of 10.7%). The most prevalent categories of systemic conditions were inflammatory joint disorders, endocrinological disorders, and syndromes. Patients with syndromes were significantly younger at the time of surgery than patients with endocrinological (P < 0.001), inflammatory joint (P = 0.003), or gastrointestinal disorders (P = 0.033). Endocrinological disorders, syndromes, and malignancies were more frequently associated with a skeletal class III malocclusion (P = 0.009, P < 0.001, and P = 0.048 respectively). Further research is needed to clarify the role of systemic conditions in the aetiology of malocclusion and postoperative outcomes.     

Masticatory function — A cineradiographic investigation: I. Position of the Bolus in Full Upper and Partial Lower Denture Cases

Abstract

Objective. The aim of the study was to evaluate the association between psychosocial aspects of temporomandibular disorders (TMD) and oral health-related quality-of-life (OHRQoL) and, secondly, to investigate the gender differences in these associations using patient and non-patient groups. Materials and methods. The sample of the study consisted of 79 patients with TMD and 70 non-patients. The data was collected by Finnish versions of the RDC/TMD Axis II profile and Oral Health Impact Profile (OHIP-14) questionnaires. The associations between Axis II profile sub-scales and OHIP prevalence were evaluated using chi-square tests, as stratified by group status (TMD patients and non-patient controls) and by gender. The association between OHIP prevalence and Axis II profile sub-scales were evaluated using logistic regression analysis, adjusted by age, gender and group. Results. OHIP prevalence (those reporting at least one problem) was 90.9% in the patient group and 33.3% in the non-patient group (p < 0.001, chi-squared test). OHIP prevalence was higher among those scoring higher on all RDC/TMD Axis II profile sub-scales, i.e. graded chronic pain status, depression and non-specific physical symptoms with pain items included and with pain items excluded. The associations were significant in the non-patient group. Women showed statistically significant associations of OHIP prevalence with all Axis II sub-scales. Among men, OHIP prevalence associated with GCPS and somatization. The logistic regression analysis showed that OHIP prevalence associated significantly with somatization and depression. Conclusions. TMD associate with OHRQoL through multiple ways, linked with depression and somatization. These findings emphasize the importance of early and effective treatment of TMD.     

Psychologic status in patients with temporomandibular disorders

PURPOSE: The aim of this study was to investigate diferrences in the prevalence of depression and somatization scores in temporomandibular disorder (TMD) patients. MATERIALS AND METHODS: One hundred fifty-four patients with single and/or multiple RDC/TMD diagnoses were classified into 7 groups based on Axis I criteria. Somatization and depression scores from the Symptom Checklist-90 were compared between groups. RESULTS: The results of this investigation indicate that patients with myofascial pain and arthralgia psychologically differed from those with disc displacement. These results were in accordance with findings that support the notion that the pain induces psychologic sequelae, at least in relation to depression and somatization. CONCLUSION: It was concluded that psychologic factors play an important role in etiopathogenesis of TMD, as demonstrated by an increase in levels of depression and somatization in TMD patients.     

Quantification of the relative risk of multiple occlusal variables for muscle disorders of the stomatognathic system

STATEMENT OF PROBLEM: There is no consensus on the association between occlusion and temporomandibular disorders (TMD). PURPOSE: The purpose of this study was to quantify the relative risk of multiple occlusal variables for muscle disorders of the stomatognathic system. MATERIAL AND METHODS: Eight occlusal features: retruded contact position (RCP) to maximum intercuspation (MI) slide length, vertical overlap, horizontal overlap, unilateral posterior reverse articulation, anterior open occlusal relationship, incisor dental midline discrepancy, mediotrusive interferences, and laterotrusive interferences, were clinically assessed by the same trained operator. The sample consisted of 81 women with a Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) axis I diagnosis of muscle disorder, for example myofascial pain, with or without limited opening, and 48 healthy women (control group). A stepwise multiple logistic regression was used to identify the significant associations between occlusal features and disease. RESULTS: A slide from the retruded contact position to maximum intercuspation > or =2 mm and mediotrusive interferences were the only 2 occlusal features significantly associated with the presence of myofascial pain according to the RDC/TMD criterion symptoms. The odds ratio for myofascial pain was 2.57 for a slide from RCP to MI > or =2 mm and 2.45 for mediotrusive interferences. The percentage of the total log likelihood for myofascial pain explained by the significant occlusal factors amounted to 10.8% (Nagelkerke's R2=0.108). The multifactorial model, including the 2 significant occlusal factors, showed an acuracy to predict disease of 66.7% (sensitivity 71.6%; specificity 58.3%). CONCLUSION: Occlusal features showed a low predictive value to detect muscle disorders of the stomatognathic system. Multifactorial complex pathologies, such as TMD, should be studied using multivariate statistical analyses, as univariate models may overestimate some resulting associations.     

Comparison of device‐supported sensorimotor training and splint intervention for myofascial temporomandibular disorder pain patients

This study was to compare the short‐term therapeutic efficacy of device‐supported sensorimotor training with that of standard splint therapy for patients with myofascial temporomandibular disorder (TMD) pain over a treatment period of 3 months. We tested the hypothesis that both types of intervention are equally effective for pain reduction. In addition, the electromyographic (EMG) activity of the temporal and masseter muscles was recorded under conditions of force‐controlled submaximum and maximum biting in intercuspation. Of consecutive patients seeking treatment for non‐odontogenic oro‐facial pain, 45 patients with myofascial TMD pain (graded chronic pain status, GCPS, I and II) were randomly assigned to 2 treatment groups (sensorimotor training and conventional splint treatment). Patients were evaluated 4 times (initial examination, 2, 6 and 12 weeks later) by use of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Electromyographic activity was recorded at the initial session and after 3 months. Ease‐of‐use of the treatment options was also evaluated. Significant (P < .0001) pain reduction (sensorimotor training 53%, splint therapy 40%) was achieved for both groups, with no significant differences (P > .05) between the groups. Force‐controlled sub‐maximum normalized electromyographic activity was significantly different between T0 and T3 for group A (sensorimotor training, P < .05) but was not significantly different for group B (splint, P > .05). For normalized maximum‐biting EMG activity in intercuspation, however, a significant increase in EMG activity was observed for group A for the masseter and temporal muscles (P < .001) and for group B for the masseter muscle only (P < .001). Moreover, sensorimotor training was significantly (P < .05) less easy to use than the splint. The results of this study confirm the pain‐reducing effect of sensorimotor training for patients with myofascial TMD pain (GCPS I and II). This innovative active treatment might be a promising option for TMD pain patients.     

骨性III类错畸形患者正颌手术前后力变化的初步研究

目的:应用计算机咬合分析系统,评价正颌手术前后骨性III类错牙合患者牙合力的变化。方法:收集15例骨性III类错牙合需正颌手术病例,利用T-ScanII牙合诊断分析系统在术前1周内、术后3个月和术后6个月时对患者的牙合力进行测定,分析患者的总牙合力(TOF)、MIP/MAX指数、牙合力不对称指数(AOF)、牙合力中心点位置(COF)及咀嚼时最大位移距离(MCOF),应用配对t检验进行比较研究。结果:术后3个月时TOF有所上升,6个月时与术前水平相比已有显著差异(P<0.05),说明患者牙合力水平已有提高。MIP/MAX指数略有下降,但6个月时增大并超过术前水平。AOF术后呈下降趋势,在3个月和6个月时均比术前显著减小(P<0.01,P<0.001)。术后COF逐渐接近正常,MCOF减小,术后6个月时均较术前明显改善,说明患者牙合力水平已有提高。结论:正颌正畸联合治疗能够改善骨性III类错牙合患者的牙合力水平及力平衡性。     

ASSESSMENT OF TEMPOROMANDIBULAR DISORDER AND OCCLUSION IN TREATED CLASS III MALOCCLUSION PATIENTS

Objective:

The aims of this study were to compare the prevalence of temporomandibular disorders (TMD) in individuals submitted to either orthodontic or ortho-surgical Class III malocclusion treatment and to assess the influence of occlusal aspects on TMD severity.

Material and methods:

The sample consisted of 50 individuals divided into two groups, according to the type of treatment (orthodontic or orthodontic with orthognathic surgery). The presence of signs and symptoms of TMD was evaluated by an anamnestic questionnaire and a clinical examination, including TMJ and muscle palpation, active mandibular range of motion, joint noises and occlusal examination.

Results:

Based on the anamnestic questionnaire, 48% had no TMD, 42% had mild TMD and 10% had moderate TMD. The presence and severity of TMD did not show any relationship with the type of orthodontic treatment (p>0.05). The chi-square test showed a positive association (p<0.05) between TMD and non-working side occlusal interferences.

Conclusion:

Based on the methodology used and the results obtained, it may be concluded that Class III orthodontic treatment was not associated with the presence of TMD signs and symptoms and the non-working side contacts can be occlusal factors of risk. There was no significant difference in TMD prevalence between the studied groups (orthodontically treated patients and patients treated with orthodontics followed by orthognathic surgery).     

Quantification and validation of predictive values of occlusal variables in temporomandibular disorders using a multifactorial analysis

STATEMENT OF PROBLEM: A consensus is lacking on the association between occlusal variables and temporomandibular disorders (TMDs). PURPOSE: This study estimated the maximum potential power of occlusal variables to differentiate patients with TMD from asymptomatic normal adult subjects. MATERIAL AND METHODS: The occlusal characteristics in 2 sets of female patients with intracapsular TMD (1993, n = 257, and 1998, n = 124) differentiated into disk displacement and osteoarthrosis subdiagnoses were compared with asymptomatic female controls (n = 51 and 47) with multiple logistic regression analysis. Significant variables and total contribution to the log likelihood were compared with the predictive value of univariate analysis, including sensitivity and specificity. RESULTS: Occlusal factors in the females (1993, 1998) explained no more than 4.8% to 27.1% of the log likelihood. In comparison to the logistic regression analysis, univariate analysis was less predictive of patients with TMD, due to notably lower sensitivity. Patients with disk displacement were mainly characterized by unilateral posterior crossbite and longer RCP-ICP slides. Patients with osteoarthrosis were most consistently characterized by longer RCP-ICP slides and larger overjet, and in part to reduced overbite. Significant relative risk for disease (odds ratio > 2:1) was mainly associated with infrequent, more extreme ranges of occlusion measurements. CONCLUSION: Occlusal factors may be cofactors in the identification of patients with TMD, but their role should not be overstated. Some occlusal variation may be a consequence of rather than a cause for TMD. Single variables have more limited value and it takes sets of adverse variables to model TMD. Combinations of variables appear to be disease specific. Some extreme ranges of occlusion were the domain of patients with TMD, but most patients were within the normal ranges.