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.

Efficacy of biofeedback therapy via a mini wireless device on sleep bruxism contrasted with occlusal splint:a pilot study

The putative causes of bruxism are multifactorial and there are no definite measures for bruxism management.The aim of this study was to evaluate the efficacy of biofeedback therapy on sleep bruxism,compared with occlusal splint.Twenty-four volunteers with sleep bruxism were divided into two groups：the GTB group that were treated with biofeedback therapy（n 512） and the GTO group that were treated with occlusal splint（n 512）.A mini pressure sensor integrated with a monitoring circuit by use of a maxillary biofeedback splint was fabricated.To foster the relaxation of the masticatory muscles and the nervous system,the wireless device received signals from bruxism events and vibrations alerted the bruxer when the threshold was exceeded.Total episodes and average duration of bruxism events during8 hours of sleep were analyzed with the monitoring program（TRMY1.0）.After 6 and 12 weeks,the episodes（P 50.001） and duration（P,0.05） in the GTB group declined dramatically.In contrast,there were no significant differences in the GTO group after the treatment（P.0.05）.Furthermore,the episodes had significant differences between the GTB group and the GTO group after the same period of treatment（P 5 0.000）.The results suggest that biofeedback therapy may be an effective and convenient measure for mild bruxers,when compared with occlusal splint therapy.The mini wireless biofeedback method may be of value for the diagnosis and management of bruxism in the future.

Treatment of condylar osteophyte in temporomandibular joint osteoarthritis with muscle balance occlusal splint and long-term follow-up:A case report

BACKGROUND Condylar osteophytes,a remodeling form of temporomandibular joint osteoarthritis(TMJ OA),mainly manifest as marginal angular outgrowths of the condyle.Previous researchers have advocated surgical removal of condylar osteophytes.Reports on the effect of occlusal splint on TMJ OA patients’joints have mostly focused on treatment with this splint,which can reduce the absorption of the affected condyle and promote repair and regeneration.However,the effect of the splint on the dissolution of condylar osteophytes has not yet been reported.CASE SUMMARY A 68-year-old female patient suffered from occlusal discomfort with left facial pain for 2 years.Cone beam computed tomography showed a rare osteophyte on top of her left condyle.She was finally diagnosed with TMJ OA.The patient refused surgical treatment and received conservative treatment with a muscle balance occlusal splint.The pain experienced by the patient on the left side of her face was relieved,and her chewing ability recovered after treatment.The osteophyte dissolved,and the condylar cortex remained stable during long-term follow-up observations.CONCLUSION The muscle balance occlusal splint could be a noninvasive means of treating condylar osteophytes in TMJ OA patients.

Influence of occlusal splint thickness on the position of mandible

Objective: To investigate the influence of occlusal splint thickness on mandibular movement. Methods: Stabilization occlusal splints of 3, 5 and 7 mm thickness were respectively used during clenching from light contact in intercuspal position and the movement of condyles and incisor point were recorded in 5 healthy subjects. Results:The condyles moved anteriorly and superiorly without wearing occlusal splint. When wearing the occlusal splints the condyles displaced anteriorly and inferiorly. The distance of displacement increased gradually with raising the thickness of splint, though the significant difference was just found in right condyle in superior- inferior movement. The condyles went again on a path of anterior and superior direction when subjects clenched from the displaced position. In right condyle the displacement was significantly greater at 7 mm splint than that at 3 mm splint both in anterior-posterior and inferior-superior direction, while in left condyle only in anterior-posterior direction. Meanwhile, the incisal point movement was larger at 7 mm splint than at 3 mm splint in inferior-superior direction. In tapping movement there were no significant differences in condyle movement between the different thickness of occlusal splint. However, the coefficient of variation in total cycle time was the greatest when wearing the splint of 7 mm. Conclusion: Occlusal splint of 7 mm has greater effect than that of 3 mm on condyle movement, but no obvious difference with occlusal splint of 5 mm. When occlusal splint of 7 mm is inserted, the stability of condyle might be influenced during tapping movement.

A Study of the electronic information monitoring of bruxism

Objective：Bruxism is the term used for teeth grinding or jaw clenching. An electronic monitor of bruxism was developed to evaluate bruxism duration and frequency. Methods： Ten cases were selected in the Department of Prosthodontics of Jiangsu Stomatological Hospital to evaluate the monitor. A stabilization occlusal splint was fabricated for each of the 10 cases. The vertical dimension for each splint was 0.5 nun lower than mandibular postural position. Some sensors had been prearranged at each splint which could transfer the variation of the biting force into electronic signals. The data of sleeping duration, grinding duration and grinding frequency were recorded with this new type of bruxism monitor, which had been specifically invented to study bruxism. Results：The data from 10 bruxism cases were collected and the results were considered reliable. Subjects nocturnal duration parameters did not change significantly from night-to-night. Conclusion：The bmxism monitor can automatically measure and record bruxism data using an occlusal splint. This device is valuable for diagnosis and evaluation of bruxism.

Effect of occlusal splints for the management of patients with myofascial pain： a randomized, controlled, double-blind study

Background Occlusal splints have been the preferred modalities in the management of myofascial temporomandibular disorders （TMDs）,but now controversy exists in reporting whether they are successful for TMDs treatments.The aim of this study was to give objective evidence to the assessment of treatment effect of occlusal splints for myofascial TMDs patients by clinical assessments and surface electromyography （sEMG） measurements of masseter muscles （MM）.Methods Thirty-six patients （12 males and 24 females） aged 16-57 （38±11） years participated in the study.All participants diagnosed with myofascial TMD were randomized into two groups （18 of each）.Patients in the first group （A） were treated with occlusal splints for 1 month,while patients in the second group （B） were treated with placebo （non-occluding palatal） splints.Clinical assessments were performed at the beginning of the study and 1 month after treatment.sEMG measurements for MM were performed at mandibular postural position （MPP） and maximum intercuspal contacted position （ICP） 1 month after the treatment.The root mean square （RMS） and the median frequency （MF） as linear indices of sEMG data were used to demonstrate muscle activity and muscle fatigue.Data were analyzed by ANOVA and post hoc SNK test.The differences were considered significant at P 〈0.05.Results It was found that 89% of group A either completely recovered （39%） or clinically improved （50%）,while only 22% of group B had a spontaneous improvement.sEMG analysis showed that at MPP,the mean of RMS value of MM in group A was lower than that of group B,which shows statistical differences （P 〈0.01）.At ICP,the RMS value of MM in group A was higher than that of group B,which shows statistical differences （P 〈0.01）.At MPP,MF value of MM in group A was higher than that of group B （P 〈0.05）.At ICP,MF value of MM was lower than that of group B （P 〈0.01）.Conclusions Occlusal splint could eliminate or improve the signs and symptoms of TMD patients with myofascial pain.sEMG analysis indicates that the wearing of occlusal splints may reduce the degree of fatigue of the masticatory muscles.The splint therapy outcome has a correlation with the electromyographic changes in the masticatory muscles.