Physiological effects of anterior repositioning splint on Temporomandibular joint disc displacement: A quantitative analysis

Abstract

Background

Anterior repositioning splints (ARS) are used primarily for the management of temporomandibular joint (TMJ) anterior disc displacement with reduction (ADDwR). However, the exact physiological effects of ARS are still unclear.

Objective

This study investigated the short and long-term effects of ARS on disc and condyle angles / positions by metric analysis.

Methods

22 subjects diagnosed with ADDwR were recruited. Maxillary full-coverage ARS were fabricated and MRI of TMJs were obtained before splint treatment, immediate post-insertion and 6 months after splint treatment. Disc-condyle relation was determined by disc-condyle angle measurement. Disc and condyle positions were described as X-Y coordinates with the summit of glenoid fossa as the origin of the coordinates.

Results

32 TMJs were classified as ADDwR and 12 were normal. Upon ARS insertion, all TMJs with ADDwR got normal disc-condyle relations. The condyles moved significantly forward and downward while the discs moved significantly backward and upward. MRI at 6 months after treatment (without ARS insertion) indicated that only 40.6% (13/32) of the joints were maintained in the normal disc-condyle relationship. The majority of condyles returned to their pre-treatment positions while the discs generally moved anteriorly again.

Conclusion

The use of ARS resulted in forward and downward condyle movement and a concurrent backward movement of the disc resulting in ideal spatial disc-condyle relationship. The stability of this relationship, however, could not be maintained in the majority of TMJs upon ARS removal. Findings explain the good short-term clinical outcomes with ARS and their relatively lower efficacy in the long-term.

This article is protected by copyright. All rights reserved.

from Rehabilitation via xlomafota13 on Inoreader http://ift.tt/2rM2RSt
via IFTTT