"Effective" TMJ and chin position changes in Class II treatment

OBJECTIVE: To evaluate the "effective" temporomandibular joint (TMJ) changes (the sum of condylar modeling, glenoid fossa modeling, and condylar position changes within the fossa), and their influence on chin position in patients with a Class II division 1 malocclusion treated orthodontically with a multibracket appliance and Class II elastics (Tip-Edge) and orthopedically with a fixed functional appliance (Herbst). MATERIALS AND METHODS: Two groups of successfully treated subjects were evaluated: Tip-Edge (n = 24) and Herbst (n = 40). The Bolton Standards served as a control group. Lateral head films obtained before treatment and after an observation period of 2.6 years (Herbst also after 0.6-year period) were analyzed. RESULTS: In comparison with the Herbst and control groups, the Tip-Edge group exhibited less favorable sagittal "effective" TMJ growth and chin position changes necessary for skeletal Class II correction. CONCLUSIONS: Orthodontic therapy with a multibracket appliance and Class II elastics seems not to have any favorable sagittal orthopedic effect on the mandible, while bite jumping with the Herbst appliance has a favorable sagittal orthopedic effect on a short-time basis.     

Predictors of signs and symptoms of temporomandibular disorders: a 20-year follow-up study from childhood to adulthood

The aim of this study was to find possible predictors of signs and symptoms of temporomandibular disorders (TMD) in a long-term perspective. Baseline questionnaire and clinical examinations focusing on function and dysfunction of the masticatory system were performed in a sample of 402 subjects 7, 11, and 15 years old. After 20 years, 320 subjects (80% of the original sample) completed a similar questionnaire as at baseline. From the oldest age group, now aged 35 years, 100 subjects (74% of the original sample) also attended a clinical examination. Three variables from the 20-year follow-up were chosen as dependent variables in logistic regression analyses, with independent variables selected from the baseline examinations. Three variables at baseline were significant predictors for reported TMJ clicking at the 20-year follow-up, tooth wear index being the strongest (odds ratio = 4.3). Reported TMJ clicking at the start was the only significant predictor for TMD symptoms without clicking 20 years later (odds ratio = 2.3). The third logistic regression model, using the Helkimo Clinical Dysfunction Score as dependent variable, resulted in four significant predictors from the baseline examinations (bruxism, oral parafunctions, TMJ clicking, and deep bite). The results indicated that some signs and symptoms might predict TMD signs and symptoms in a long-term perspective. However, it cannot be concluded from this study whether these symptoms recorded in childhood--oral parafunction, tooth wear, TMJ clicking, and deep bite--can be used for predicting manifest TMD in adult age.     

Predictors of signs and symptoms of temporomandibular disorders: a 20-year follow-up study from childhood to adulthood

The aim of this study was to find possible predictors of signs and symptoms of temporomandibular disorders (TMD) in a long-term perspective. Baseline questionnaire and clinical examinations focusing on function and dysfunction of the masticatory system were performed in a sample of 402 subjects 7, 11, and 15 years old. After 20 years, 320 subjects (80% of the original sample) completed a similar questionnaire as at baseline. From the oldest age group, now aged 35 years, 100 subjects (74% of the original sample) also attended a clinical examination. Three variables from the 20-year follow-up were chosen as dependent variables in logistic regression analyses, with independent variables selected from the baseline examinations. Three variables at baseline were significant predictors for reported TMJ clicking at the 20-year follow-up, tooth wear index being the strongest (odds ratio = 4.3). Reported TMJ clicking at the start was the only significant predictor for TMD symptoms without clicking 20 years later (odds ratio = 2.3). The third logistic regression model, using the Helkimo Clinical Dysfunction Score as dependent variable, resulted in four significant predictors from the baseline examinations (bruxism, oral parafunctions, TMJ clicking, and deep bite). The results indicated that some signs and symptoms might predict TMD signs and symptoms in a long-term perspective. However, it cannot be concluded from this study whether these symptoms recorded in childhood - oral parafunction, tooth wear, TMJ clicking, and deep bite - can be used for predicting manifest TMD in adult age.     

Herbst双期拔牙矫治对颞下颌关节位置影响的CBCT研究

目的:探讨Herbst双期拔牙矫治对颞下颌关节位置关系的影响.方法:纳入15例恒牙列早期安氏Ⅱ类错(牙合)下颌后缩患者,一期矫治采用Herbst矫治器,然后拔除每位患者的4个前磨牙;二期矫治采用edgewise固定矫治器.在Herbst矫治器矫治前两周(T1期)、Herbst矫治器初戴入矫治时(T2期)、Herbst矫治器拆除时(T3期)及二期固定矫治器拆除时(T4期)分别拍摄锥形束CT(cone beam computed tomography,CBCT).应用InvivoDental软件对CBCT图像进行三维重建,再对颞下颌关节间隙进行测量,并进行统计分析.结果:T1-T2-T3期,关节前间隙先减小后增大,关节上间隙、关节后间隙先增大后减小;T3-T4期,关节上、后间隙进一步减小,关节前间隙无明显变化;与T1期比,T4各关节间隙的变化均无明显差异.结论:髁突在关节窝中的位置在Herbst矫治开始时向前下移位,一期功能矫治结束时尤其双期矫治结束时几乎回到了治疗前的位置.     

Mandibular articular disk position changes during Herbst treatment: a prospective longitudinal MRI study.

The aim of this prospective longitudinal study of 15 consecutively treated Class II malocclusions was to assess any possible changes in the relative position of the articular disk to the condyle during different phases of Herbst therapy. Using a disk position index, parasagittal MRIs (central, medial and lateral slices) of the right and left TMJ were analyzed at five occasions: before Herbst treatment (T1), at start of treatment when the appliance was placed (T2), after 6 weeks of treatment (T3), after 13 weeks of treatment (T4), and after 7 months of treatment when the appliance was removed (T5). In all subjects Herbst treatment resulted in Class I or overcorrected Class I dental arch relationships. Condyle position was on average unchanged during Herbst treatment (T1 to T5). Before treatment (T1) the articular disk was in a slight protrusive position relative to the condyle. At start of treatment (T2) the mandible was advanced to an incisal edge to edge position. Because of the physiologic relative movement of disk and condyle on mandibular protrusion the disk attained a pronounced retrusive position. At the end of treatment (T5), the disk had almost returned to its original pretreatment position. In several cases, however, a slight retrusive disk position prevailed. In conclusion, Herbst treatment did not result in any adverse changes in articular disk position. On the contrary, the Herbst appliance could possibly be useful in the therapy of patients with anterior disk displacement.     

Stability of anterior crossbite correction: A randomized controlled trial with a 2-year follow-up

Objective:To compare and evaluate the stability of correction of anterior crossbite in the mixed dentition by fixed or removable appliance therapy.Material and Methods:The subjects were 64 consecutive patients who met the following inclusion criteria: early to late mixed dentition, anterior crossbite affecting one or more incisors, no inherent skeletal Class III discrepancy, moderate space deficiency, a nonextraction treatment plan, and no previous orthodontic treatment. The study was designed as a randomized controlled trial with two parallel arms. The patients were randomized for treatment with a removable appliance with protruding springs or with a fixed appliance with multibrackets. The outcome measures were success rates for crossbite correction, overjet, overbite, and arch length. Measurements were made on study casts before treatment (T0), at the end of the retention period (T1), and 2 years after retention (T2).Results:At T1 the anterior crossbite had been corrected in all patients in the fixed appliance group and all except one in the removable appliance group. At T2, almost all treatment results remained stable and equal in both groups. From T0 to T1, minor differences were observed between the fixed and removable appliance groups with respect to changes in overjet, overbite, and arch length measurements. These changes had no clinical implications and remained unaltered at T2.Conclusions:In the mixed dentition, anterior crossbite affecting one or more incisors can be successfully corrected by either fixed or removable appliances with similar long-term stability; thus, either type of appliance can be recommended.     

Discectomy of the temporomandibular joint: 3-year follow-up as a predictor of the 10-year outcome.

PURPOSE: The study goal was to evaluate whether the 3-year follow-up evaluation of temporomandibular joint (TMJ) discectomy in a consecutive series of patients with TMJ internal derangement was a reliable predictor for the 10-year outcome of the operation. MATERIAL AND METHODS: Twenty-nine patients with TMJ internal derangement were treated with discectomies, 6 bilaterally and 23 unilaterally. The patients were followed up for 10 years. RESULTS: The dropout rate was zero at the 3-year follow-up, and 5 patients (17.2%) had dropped out at the 10-year follow-up. There was a significant reduction in the median visual analog scale recordings, and all but 1 patient reported reduction in the pain score. Mandibular motion increased significantly after 3 years, and similar or improved recordings were made at the 10-year follow-up. All but 5 patients showed an increased motion at the 10-year follow-up compared with the preoperative motion. The only complication seen at the 10-year follow-up examination was a slight anesthesia of the auriculotemporal nerve in 1 patient. All types of additional therapy decreased significantly after the operations. CONCLUSIONS: Discectomy of the TMJ may significantly reduce pain and improve function in patients with internal derangement on a long-term basis. The 3-year follow-up examination proved to be a reliable predictor of the 10-year results.     

A 6- and 12-month follow-up of appliance therapy in TMD patients: a follow-up of a controlled trial

PURPOSE: This study compared the long-term effects of treatment with a stabilization appliance and treatment with a control appliance in patients with temporomandibular disorders (TMD). MATERIALS AND METHODS: In a controlled trial, 60 TMD patients with temporomandibular joint (TMJ) pain were evaluated after 10 weeks of treatment with either a stabilization appliance or a control appliance. At the 10-week follow-up, the 60 patients were assigned to one of three groups according to their demand for treatment. Group T, the treatment group, comprised 30 patients treated with a stabilization appliance; group C, the control group, comprised nine patients treated with a control appliance; and group M, the mixed treatment group, comprised 21 patients treated with first a control appliance and then a stabilization appliance. Signs and symptoms were evaluated in all three groups at 6- and 12-month follow-ups. RESULTS: At the 6- and 12-month follow-ups, a significant reduction in TMJ pain as measured on a visual analogue scale was found in all three groups, and a significant decrease in signs and symptoms was found in groups T and M. CONCLUSION: After 6 and 12 months of use, the stabilization appliance was found to still be effective in the alleviation of signs and symptoms in patients with TMD. Many patients in group C changed to a stabilization appliance at the 1 0-week follow-up, which significantly reduced the number of patients in this group. Most patients reported positive change in overall subjective symptoms in this trial. The stabilization appliance can therefore be recommended for patients with TMD.     

Herbst appliance effects on pharyngeal airway ventilation evaluated using computational fluid dynamics

Objective:To evaluate the effect of a Herbst appliance on ventilation of the pharyngeal airway (PA) using computational fluid dynamics (CFD).Materials and Methods:Twenty-one Class II patients (10 boys; mean age, 11.7 years) who required Herbst therapy with edgewise treatment underwent cone-beam computed tomography (CBCT) before and after treatment. Nineteen Class I control patients (8 boys; mean age, 11.9 years) received edgewise treatment alone. The pressure and velocity of the PA were compared between the groups using CFD based on three-dimensional CBCT images of the PA.Results:The change in oropharyngeal airway velocity in the Herbst group (1.95 m/s) was significantly larger than that in the control group (0.67 m/s). Similarly, the decrease in laryngopharyngeal airway velocity in the Herbst group (1.37 m/s) was significantly larger than that in the control group (0.57 m/s).Conclusion:The Herbst appliance improves ventilation of the oropharyngeal and laryngopharyngeal airways. These results may provide a useful assessment of obstructive sleep apnea treatment during growth.     

Incidence and prevalence of temporomandibular joint pain and dysfunction. A one-year prospective study of university students

Objective. The aims of this study were to investigate the incidence and recovery of temporomandibular joint (TMJ) pain and dysfunction during a 1-year period, and to examine factors associated with TMJ signs and symptoms. Material and Methods. The study population comprised 371 dental students examined at the start of education, out of which 308 were re-examined after 1 year. Case histories were collected with the aid of a questionnaire. The clinical examination involved TMJ mobility, TMJ pain, TMJ sounds, morphological and functional dental occlusion. Results. The 1-year incidence of TMJ signs and/or symptoms was 12%, with no statistically significant difference between men and women. Reported TMJ sounds (10%) and clinically registered TMJ pain (8%) reached the highest incidence rates. Approximately a quarter of those who had TMJ signs and/or symptoms at baseline had recovered at follow-up. Subjects with a non-symptomatic TMJ were significantly more often found among men and among those with bilateral contacts in centric relation, a normal transverse inter-maxillary relationship, and a stabile mandibular position in centric occlusion. Conclusion. The 1-year incidence of TMJ pain and/or dysfunction was high among 1st-year university students. The persistence of signs and symptoms during the observation period was related to gender, while incidence and disappearance of symptoms were not. Dental occlusion was not rejected as a possible concurrent factor in relation to TMJ pain and/or dysfunction among university students.     

A 3-year study of patients with tinnitus and jaw muscle tenderness

Objective: This study evaluated three-year results of treatment with an interocclusal appliance in 89 tinnitus patients with jaw muscle tenderness.

Methods: Subjective tinnitus severity was recorded using a visual analog scale (VAS). The number of tender muscles was registered. The patients were followed annually. After three years, 64 patients were examined (72%).

Results: Tinnitus severity at baseline was high (mean VAS value 68.3). After one year, the VAS values were substantially lower (mean 37.4; p < 0.001). During the following two years, there were no significant changes in VAS values. The mean number of tender muscles decreased from seven to two after one year and remained at this number for up to three years.

Conclusion: In many tinnitus patients with signs of temporomandibular disorders (TMDs), intraoral splint therapy reduced tinnitus severity and jaw muscle symptoms. The favorable results after one year remained for up to three years without significant changes.     

Long-term effects of the Herbst appliance on the craniomandibular system with special reference to the TMJ

The purpose of this study was: (1) to analyse the long-term clinical implications of Herbst treatment on the masticatory system, and (2) to analyse the radiographic appearance of the temporomandibular joints at the time of follow-up using lateral tomography of the right and left TMJ. The sample consisted of 19 consecutive male subjects with a Class II, Division 1 malocclusion treated with the Herbst appliance for an average period of 7 months. The patients were reinvestigated at the end of the growth period (an average of 7.5 years after treatment). The anamnestic, clinical, and radiographic findings revealed that Herbst treatment did not seem to have any long-term adverse effects on the craniomandibular system.     

Motivation, Acceptance and Problems of Invisalign® Patients

Abstract Aim: This study examined how well patients accepted and to what extent they were impaired by Invisalign^® treatment. Patients and Methods: Fifty-four consecutive patients received a questionnaire with 12 questions after 3 to 6 months of Invisalign^® treatment. They were given a choice of three responses for each question. Apart from personal data, the questionnaire covered the following parameters: adaptation time, occurrence and duration of pain, possible speech impairment, lingual and mucosal irritations, temporomandibular joint (TMJ) problems and subjective assessment of the success of therapy thus far and the quality of information initially provided. Results: 78% of those interviewed were females. The highest percentage of patients (44%) were between 20 and 30 years of age. 83% got used to their aligners within one week. 35% had no pain and 54% mild pain while wearing them. This pain usually lasted for 2 to 3 days following insertion of a new aligner. 46% of the patients experienced no speech impairment. 93% felt so secure with their aligners that they felt not at all inhibited about speaking. The majority noticed no narrowing of the lingual space (76%) or irritation of the lingual or buccal mucosa (70%). However, 6% had strong irritations. 44% of the patients had difficulty chewing, mainly because the teeth were sensitive to pressure or had food particles caught between them due to temporary gaps. TMJ problems in terms of clicking were reported by 8% of the patients, although the clicking had existed before therapy initiation. None of the patients had TMJ pain. At the time of the interview, 89% of the patients were satisfied with the progress of therapy. All patients considered themselves well or very well informed about the treatment. Conclusions: Invisalign^® therapy seems particularly attractive to a clientele comparable to that for the lingual technique. Patients show high acceptance, since they become accustomed to the aligners very quickly and do not suffer much impairment. If indicated, Invisalign^® therapy should thus be considered an alternative to the lingual technique for esthetically-demanding patients. This applies especially to patients who cannot be treated by the lingual technique because of the inevitable speech impairment.     

A prospective study on the clinical effectiveness of the stainless steel crown Herbst appliance

ObjectivesTo evaluate the clinical performance of the stainless steel crown Herbst (cHerbst) used as a single appliance for a single phase therapy.Materials and methodsA total of 180 consecutive Class II patients were treated with cHerbst for one year and followed up one year after the end of treatment.ResultsClass I relationship was achieved in all 175 patients who finished the functional phase of treatment, 58 patients continued treatment with fixed appliances while 21 patients (12%) showed relapse. Seventy two patients (41.1%) obtained and maintained stable Class I relationship one year after treatment with the cHerbst appliance used as a single appliance. Altogether 46 episodes of appliance breakages were observed and most of them could be repaired at the chair side. Patients’ questionnaire revealed that in general the appliance was easy to tolerate and did not cause esthetic or functional problems.ConclusionsThe crown Herbst appliance is a viable therapeutical option in patients with Class II malocclusions and it is characterized by low complication rate along with good patient compliance.     

Amount and direction of temporomandibular joint growth changes in Herbst treatment: a cephalometric long-term investigation

The amount and direction of condylar growth, glenoid fossa displacement, and "effective" temporomandibular joint (TMJ) changes (a summation of condylar growth, glenoid fossa displacement, and condylar position changes within the fossa) were analyzed in 35 Class II, Division 1 malocclusions (23 boys and 12 girls) treated with the Herbst appliance. Lateral head films in habitual occlusion and with the mouth wide open from before (T1) and after 7.5 months of Herbst treatment (T2) as well as 7.5 months (T3) and three years (T4) after treatment were evaluated. As a control group, a sample of 12 untreated male Class II Division I malocclusions was used during a 7.5-month time period corresponding to the treatment period (T2-T1) of the Herbst cases. The results revealed that during the treatment period (T2-T1) condylar growth was directed posteriorly about twice the amount as in the control subjects, and the fossa was displaced in an anterior inferior direction. The effective TMJ changes showed a pattern similar to condylar growth but were more pronounced. During the first posttreatment period (T3-T2), all TMJ changes reverted. The glenoid fossa was displaced backward; the amount of condylar growth and effective TMJ changes was reduced, and the changes were more superiorly directed. During the second posttreatment period (T4-T3), all TMJ changes were considered physiological. Conclusion: During Herbst treatment, the amount and direction of TMJ changes (condylar growth, fossa displacement, and effective TMJ changes) were only temporarily affected favorably by Herbst treatment.     

Effective temporomandibular joint growth and chin position changes: Activator versus Herbst treatment. A cephalometric roentgenographic study

In 138 successfully treated Class II division 1 patients (40 Activator and 98 Herbst) effective temporomandibular joint (TMJ) growth changes (a summation of condylar remodelling, glenoid fossa remodelling, and condylar position changes within the fossa), and their influence on the position of the chin and the rotation of the mandible were analysed retrospectively. Lateral head films in habitual occlusion from before and after an average treatment period of 2.6 years for the Activator patients and 0.6 years for the Herbst patients were evaluated. Two different treatment changes were assessed: (1) overall growth changes and (2) treatment effects (overall growth changes minus age-related normal growth values: Bolton Standards). The comparison between the Activator and the Herbst group revealed larger effective TMJ and chin changes during Activator therapy due to the longer observation period (2.6 years versus 0.6 years). The treatment effects showed marked group differences for both the amount and direction of effective TMJ changes. The changes were vertical and slightly anterior in the Activator group, and predominantly posterior in the Herbst group. Concerning the chin changes, the treatment effects for the Herbst group exceeded those for the Activator group in both directions, caudally and anteriorly. The Activator group showed an anterior rotation and the Herbst group a slight posterior rotation of the mandible. The present investigation revealed that the effective TMJ and chin changes were increased by both Activator and Herbst treatment. However, the Herbst appliance renders more favourable sagittally orientated treatment effects in a much shorter period of time compared with the Activator.     

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.     

Soft versus hard occlusal splint therapy in the management of temporomandibular disorders (TMDs)

Aim

To compare between soft and hard occlusal splint therapy for the management of myofacial pain dysfunction (MPD) or internal derangement (ID) of the temporomandibular joint (TMJ) with reciprocal clicking.

Patients and methods

This study included 50 patients (age range: 24–47 years) who had been diagnosed with MPD or ID of the TMJ in the form of reciprocal clicking. Patients were divided into two groups. They were treated for 4 months with either a vacuum-formed soft occlusal splint constructed from 2-mm-thick elastic rubber sheets (soft splint group) or a hard flat occlusal splint fabricated from transparent acrylic resin (hard splint group). Monthly follow-up visits were performed during the treatment period. Before treatment and 1, 2, 3 and 4 months after treatment, the dentist measured all parameters of TMJ function (pain visual analog scores, tenderness of masticatory muscles, clicking and tenderness of the TMJ, and range of mouth opening).

Results

All parameters of TMJ function showed significant improvement in both groups during the follow-up period, with a statistically significant difference between the two groups at the 4-month follow-up visit.

Conclusions

Both forms of occlusal splints (soft and hard) improved TMJ symptoms in patients with MPD or ID of the TMJ. However, the soft occlusal splints exhibited superior results after 4 months of use.     

Outcomes of temporomandibular joint disorder therapy: observations over 13 years

Objective. To evaluate the outcome of temporomandibular joint (TMJ) disorder therapy with different kinds of splints. Methods. One-hundred-and-twenty-nine patients with TMJ disorders and meeting the primary selection criterion of reporting pain in the TMJ region were clinically evaluated. Magnetic resonance imaging of the TMJ was performed at baseline 1993–94. A protrusion splint was used whenever joint clicking could be eliminated by protrusion. In the other cases, a pivot or a Michigan splint was inserted. Re-evaluation of the patients after 12 months included a clinical examination. After 5 and 13 years, all patients were examined by means of a questionnaire. Results. Pain was significantly reduced in the case of more than two-thirds of the patients 1 year after the first consultation. After 5 and 13 years, the percentages of patients with reported pain had increased only slightly. However, the therapy did not reduce joint noises or mouth opening. The prevalence of joint noises was reduced to less than a quarter after 1 year, but during the next 13 years increased to the former level. Initially, one-third of the patients had mouth-opening reduction. This proportion dropped to one-third of these cases after 1 year, but increased to 40% after 13 years. Conclusions. Treatment using splints reduced pain in approximately two-thirds of the patients, but with no difference between the three types of splints used.     

Does bite-jumping damage the TMJ? A prospective longitudinal clinical and MRI study of Herbst patients

The aim of this prospective longitudinal study of 62 consecutively treated Class II malocclusions was to determine whether bite-jumping causes temporomandibular disorders (TMD). The function of the temporomandibular joint (TMJ) was assessed anamnestically, clinically, and by means of magnetic resonance images (MRIs) taken before (T1), after (T2), and 1 year after (T3) Herbst treatment. Average treatment time with the Herbst appliance was 7.2 months. In all subjects, Herbst treatment resulted in a Class I or overcorrected Class I dental arch relationship. Thereafter, treatment was continued with a multibracket appliance. The condyle was positioned significantly forward during treatment but returned to its original position after removal of the Herbst appliance. A temporary capsulitis of the inferior stratum of the posterior attachment was induced during treatment. Over the entire observation period from before treatment to 1 year after treatment, bite-jumping with the Herbst appliance: (1) did not result in any muscular TMD; (2) reduced the prevalence of capsulitis and structural condylar bony changes; (3) did not induce disc displacement in subjects with a physiologic pretreatment disc position; (4) resulted in a stable repositioning of the disc in subjects with a pretreatment partial disc displacement with reduction; and (5) could not recapture the disc in subjects with a pretreatment total disc displacement with or without reduction. A pretreatment total disc displacement with or without reduction did not, however, seem to be a contraindication for Herbst treatment. In conclusion, bite-jumping using the Herbst appliance does not have a deleterious effect on TMJ function and does not induce TMD on a short-term basis.