The immediate effect of temporary silicone splint application on symmetry of masticatory muscle activity evaluated using surface electromyography

Abstract Introduction Muscle activity is regarded as an important factor associated with the temporomandibular disorder (TMD). Detecting muscle imbalance is an essential part of a treatment strategy. Aim The aim of the present study was to evaluate the influence of temporary silicon splint application on the symmetry of masticatory muscle activities during clenching using surface electromyography. Material and methods Thirty-five full dentate, normo-occlusion and similarly aged (25.1 ± 2.3 years old) female subjects were recruited. The electrical activity of the temporalis anterior (TA) and masseter muscle (MM) of the right and left side was recorded simultaneously during clenching isometric activity. The eight-channel electromyograph BioEMG III, compatible with BioPAK Measurement System, was used for the recording. To describe the asymmetry of the TA, MM muscles and TA–MM asymmetry for right and left side, a symmetry index (SI) was calculated. Results and discussion Mean SI of MM was significantly higher during splint application measurement (SAM), in comparison to non-splint measurement (NSM) (NSM: 67.28 ± 19.63%; SAM: 78.26 ± 17.68%; mean difference: 10.97%; P Conclusions Application of temporary silicon splint reduces double-sided imbalance of MMs during clenching. The mechanism of action of silicone splints may be partly explained by their effect on masticatory muscles activity. Chair-side fabricated silicone splint may be used as a cost-effective, simple method for initial treatment of TMD. The influence of temporary silicon splint application on long-term effects of treatment requires further research.