Anterior Repositioning Splint Therapy Research Articles

Step-back anterior repositioning splint retraction for temporomandibular joint disc displacement with reduction in adult patients.

Anterior repositioning splint (ARS) is used to treat temporomandibular joint (TMJ) disc displacement with reduction (DDwR). However, high recurrence rate remains a problem especially in patients with unstable occlusions. This study optimised standard ARS therapy and proposed a step-back ARS retraction (SAR) method in adult patients with DDwR. Dental examinations and magnetic resonance imaging of TMJ were obtained before treatment (T0), 1 to 3 months (T1), 3 to 6 months (T2) and 6 to 12 months (T3) during treatment in 48 adults (average age 27.1 ± 5.7 years). After 3 months of basic ARS wearing, personalised treatment for patients with normal disc-condyle relationship was prescribed depending on bilaminar zone adaptations and severity of molar openbite. SAR which required sequential ARS wearing was designed for patients with deep overbite/overjet until retrodiscal tissue adaptations and stable occlusions were achieved. The maximum interincisal opening was increased from 44.3 ± 6.9 to 45.3 ± 6.3 mm (p < .01), and joint pain was alleviated after ARS treatment. The overall success rate of ARS wearing was 92.1% (58/63) featured by a recaptured disc. Fifteen patients who underwent SAR therapy all showed bilaminar zone adaptations in the end, and one patient had positive condylar bone remodelling. ARS treatment could improve mouth opening and joint symptoms in adult DDwR patients. SAR method was suitable for treating DDwR patients with deep overbite and overjet and improved retrodiscal tissue adaptations and condylar bone remodelling.

Efficacy of Arthrocentesis and Anterior Repositioning Splints in Treatment of Internal Derangement of TMJ: A Prospective Clinical Study.

The aim of this study is to assess the efficacy of double puncture arthrocentesis and anterior repositioning splints in the treatment of internal derangement of temporomandibular joint. 35 patients with mean age of 36.6 years±10.2 years diagnosed with unilateral TMD who fell into Wilkes stage 2 and disc displacement with reduction with intermittent locking described by RDC/TMD were treated with Nitzan's double puncture arthrocentesis and were given a anterior repositioning hard splint. The parameters following parameters were assessed at intervals of 1 week, 2 weeks, 1 month, 3 months and 6 months: pain, maximum inter-incisal mouth opening, Joint noise/click. Statistically significant (p < 0.001) improvements were seen at all recorded intervals in all observed parameters. Simultaneous arthrocentesis and anterior repositioning splint therapy is effective in alleviating pain and improving mouth opening without discomfort in patients with unilateral painful TMD showing disc displacement with reduction with intermittent locking.

The effect of anterior repositioning splint therapy on maximum bite forces in patients with disc interference disorders

Objective To evaluate the effect of anterior repositioning splint (ARS) on maximum bite force (MBF) values in patients with disc interference disorders (DID). Material and methods Twenty-two patients with disc interference disorders and 22 healthy subjects participated in to study. The Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I have been used to diagnose DID patients. All patients received ARS therapy for 6 weeks. The MBF measurement was performed with Flexi-Force piezo-resistive sensors for both healthy subjects and patients before and after ARS therapy. Results A significant difference was recorded by the increase of the mean MBF values after the use of the ARS in the patient with disc derangements (p < .05). Conclusions APS therapy is efficient for eliminating pain and increasing MBF of the patients with DID. In addition, the use of FlexiForce sensors may be a practical solution to assess the bite force in the clinical setting.

An Overview of Anterior Repositioning Splint Therapy for Disc Displacement-related Temporomandibular Disorders.

Anterior repositioning splint (ARS) therapy is considered one of the most effective therapies for treating disc displacement-related temporomandibular disorders (TMDs), which account for a large proportion of TMD cases. Owing to the wide application of this therapy, the exact mechanism of remission has increasingly drawn attention. Given that practitioners have different views on ARS therapy, its indications are broadened, and operating methods diverged. This review attempts to provide an overview of ARS therapy and helps practitioners establish indications and suitable operating methods. Representative views in the past 10 years were summarised, and conclusions were drawn as follows: The mechanism of ARS therapy is mainly attributed to internal derangement correction, improvement of stress distribution and recently reported joint remodeling. It has an evident effect in the short term, and the most prevalent operating methods are protruding the mandible to the edge-to-edge position and wearing the ARS for 24 hours daily for 3-6 months. However, long-term stability is not optimal, and thus indications should be selected carefully. Notably, most of the clinical studies in this field are case analyses with low-quality evidence. Well-designed RCTs are required to further validate relevant theories.

Evolutionary Spectral Analysis of Temporomandibular Joint Sounds Before and After Anterior Repositioning Splint Therapy in Patients with Internal Derangement.

To determine the effectiveness of anterior repositioning splint (ARS) therapy on elimination of temporomandibular joint (TMJ) sounds in patients with internal derangement. A total of 26 patients with 44 TMJs with internal derangement according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) were selected. These patients used an ARS for 6 weeks. The sounds of both the right and left TMJs were recorded with a specifically developed sound recording system before and after ARS therapy. The evaluation of sound was performed using evolutionary spectral analysis on the program MATLAB. Parameters such as sound type, amplitude, duration, and energy were evaluated in a time-frequency analysis. Changes in mean amplitude levels of opening/closing TMJ sounds before therapy and 6 weeks after insertion of splints were compared using paired-samples t test. The level of significance was set at 5%. The patients showed a decrease in the mean amplitude and energy values of opening/closing sounds after 6 weeks of ARS use (P < .05). According to evolutionary spectral analysis, the use of ARS was efficient for 7 of 19 right joints (37%) and 11 of 25 left joints (44%). The results suggest that the use of 6-week ARS reduced amplitude and energy parameters of TMJ sounds; however, it did not completely eliminate TMJ sounds.

Condylar repair and regeneration in adolescents/young adults with early-stage degenerative temporomandibular joint disease: A randomised controlled study.

Anterior repositioning splint (ARS) can facilitate regenerative condylar remodelling. To determine the effect of ARS on osseous condylar changes in adolescents/young adults with early-stage degenerative joint disease (DJD). Sixty-nine patients with early-stage temporomandibular joint (TMJ) DJD based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) and cone beam computed tomography (CBCT) imaging were recruited and randomly allocated to two treatment groups: (a) conservative therapy with ARS and (b) conservative therapy without ARS. Subjects with acute TMJ closed-lock had their displaced discs physically reduced by mandibular manipulation prior to ARS therapy. Clinical and CBCT data of 59 patients (86.4% females, mean age 17.95±4.53years, 67 joints) were attained pre- and at 6 or 12months post-treatment. Osseous changes after treatment were categorised into (a) progressed, (b) unchanged, (c) repaired (remodelled without new bone formation) and (d) regenerated (remodelled with new bone formation). Statistical analysis including chi-square test, independent samples t test or Mann-Whitney U test was conducted. About 85.5% of patients (59/69) completed the study, with 28 subjects (32 joints) in the splint group and 31 (35 joints) in the control group. The occurrence of condylar repair and regeneration was significantly higher with ARS (78.1%/[25/32] of joints) when compared to control group (48.6%/[17/35]) (P<0.05). Moreover, condylar regeneration was exclusively observed in 50%/(16/32) of joints with ARS. For the 14 joints in splint group that received physical TMJ closed-lock reduction, 85.7%/(12/14) exhibited condylar regeneration. The splint group (3.1%/[1/32]) also had significantly lower incidence of progressive TMJ degeneration than the control (37.1%/[13/35]) (P<0.001). Condylar repair and regeneration in early-stage TMJ DJD are possible, and ideal spatial disc-condyle relationship appears important. The possibility of restoring TMJ form/structure by ARS therapy presents an attractive area of new basic science and clinical research (Bone defect repair in early osteoarthrosis of temporomandibular joint by joint distraction therapy: A randomized controlled trial/ChiCTR-TRC-14005172).

Residents' journal review

Residents' journal review

Orthodontic Treatment for the TMJ Patient Following Splint Therapy to Stabilize a Displaced Disk(s): A Systemized Approach. Part I, TMJ Orthodontic Diagnosis

Orthodontic treatment for a patient who has had a displaced disk or disks and has been stabilized by anterior repositioning splint therapy presents the dentist with a difficult orthodontic problem. Frequently, there is a posterior open bite present, with the anterior teeth only occluding in the stabilized TMJ position upon removal of the splint. The current articles (Part I of II presented here) will present an organized TMJ/orthodontic diagnosis (Part I) and orthodontic treatment method (Part II, to be presented in the next journal) to properly treat these patients to a consistent stabilized occlusion compatible with the TMJ splint stabilized position.

Surface electromyographic patterns of masticatory, neck, and trunk muscles in temporomandibular joint dysfunction patients undergoing anterior repositioning splint therapy

The aim of this study was to investigate the surface electromyographic (sEMG) activity of neck, trunk, and masticatory muscles in subjects with temporomandibular joint (TMJ) internal derangement treated with anterior mandibular repositioning splints. sEMG activities of the muscles in 34 adult subjects (22 females and 12 males; mean age 30.4 years) with TMJ internal derangement were compared with a control group of 34 untreated adults (20 females and 14 males; mean age 31.8 years). sEMG activities of seven muscles (anterior and posterior temporalis, masseter, posterior cervicals, sternocleidomastoid, and upper and lower trapezius) were studied bilaterally, with the mandible in the rest position and during maximal voluntary clenching (MVC), at the beginning of therapy (T0) and after 10 weeks of treatment (T1). Paired and Student's t-tests were undertaken to determine differences between the T0 and T1 data and in sEMG activity between the study and control groups. At T0, paired masseter, sternocleidomastoid, and cervical muscles, in addition to the left anterior temporal and right lower trapezius, showed significantly greater sEMG activity (P = 0.0001; P = 0.0001; for left cervical, P = 0.03; for right cervical, P = 0.0001; P = 0.006 and P = 0.007 muscles, respectively) compared with the control group. This decreased over the remaining study period, such that after treatment, sEMG activity revealed no statistically significant difference when compared with the control group. During MVC at T0, paired masseter and anterior and posterior temporalis muscles showed significantly lower sEMG activity (P = 0.03; P = 0.005 and P = 0.04, respectively) compared with the control group. In contrast, at T1 sEMG activity significantly increased (P = 0.02; P = 0.004 and P = 0.04, respectively), but no difference was observed in relation to the control group. Splint therapy in subjects with internal disk derangement seems to affect sEMG activity of the masticatory, neck, and trunk muscles.

Changes in vertical tooth position and face height related to long term anterior repositioning splint therapy.

This study evaluates whether extended full-time wear of a partial coverage mandibular anterior repositioning splint (MORA) causes intrusion of posterior teeth and determines the effect on jaw position. Sixty-four patients from two private orthodontic practices were studied using cephalometric radiographs to measure vertical change in position of the anterior and posterior teeth and the mandible. The splint wear time ranged from a minimum of one half year to a maximum of 4.8 years, with a mean of 1.33 years. No significant change was recorded in the distance from the mandibular molar to the mandibular plane. On average, the maxillary incisor and maxillary molar extruded about 1 mm, while the mandibular molar was unchanged and the mandibular incisor intruded about 0.6 mm. Posterior face height increased an average of 1.6 mm, and anterior face height increased an average of 2.7 mms. In 20% of the patients, intrusion of the mandibular molars of 1 mm or more occurred. In 41%, extrusion of the maxillary incisors of 1 mm or more was noted. Intrusion of the upper molars or extrusion of the lower incisors occurred in only 5% of the patients. The data indicates that only a very small proportion of patients having long term splint therapy using the MORA have clinically significant molar intrusion. Change in mandibular position was expressed in a vertical increase in posterior and anterior face height. Only very small changes occurred in antero-posterior position.

Long-term treatment of disk-interference disorders of the temporomandibular joint with anterior repositioning occlusal splints

Forty patients with three different types of symptomatic disk-interference disorders were treated with anterior repositioning splint therapy for 8 weeks. At the end of that period 80% of the patients were free of joint sound and pain. Each patient's splint was then gradually modified until the patient's original occlusal condition was reestablished. Each patient was then allowed to function in that position. The patients were reevaluated an average of 2 1/2 years later. Seventy-five percent of the patients had no joint pain and 66% had a return of joint sounds. Sixty-six percent of the patients did not find the need to seek additional treatment for jaw pain and dysfunction.