The effects of stabilization splint treatment on the volume of masseter muscle in sleep bruxism patients.

Objective The aim of this study was to evaluate, quantitatively, the volumetric effects of stabilization splint therapy on the masseter muscle of sleep bruxism (SB) patients. Methods The magnetic resonance (MR) images of 16 SB patients diagnosed by polysomnography (PSG) who used stabilization splints for four months were obtained before and after the therapy. The masseter muscle volume was calculated using Cavalieri's principle on the MR images. Results After the splint therapy, the mean volume of the masseter muscle did not reduce significantly. The fat and/or water content of the muscles did not change either. Discussion The stabilization splint therapy had no effect on the volume, fat and/or water content of the masseter muscle; however the discomfort was reduced in the patients. Although the effect of splint therapy is not fully understood, the non-invasive and reversible stabilization splint can be used in SB patients because of its relaxation effect on muscles.