Abstract: Objective: To evaluate the effect of low-frequency repetitive transcranial magnetic stimulation (rTMS) on patients with sleep bruxism. Methods: 30 patients with sleep bruxism participated in this study. The hot spot was defined at the spot where the AMT was elicited by the minimum stimulus intensity produced five discrete MEPs clearly. The active motor threshold was defined by the minimum stimulus intensity. The low-frequency rTMS was given at the hot spot using 90%AMT with 20 minutes on each side for a total of 40 minutes, for 7 consecutive days. Two days before and after the treatment, the patients were asked to ware a very thin splint made by Bruxchecker at night. Meanwhile, muscle palpation of the superficial and deep masseter muscle, and the anterior, middle and posterior portions of the temporalis was performed, and the scores of the evaluation of palpation given by the patients themselves were recorded. Results: Before the treatment, there was no statistically significant difference in the area of abrasion on the surface of the Bruxchecker and the scores of all muscle palpation. After 7 days of low-frequency rTMS treatment, the area of abrasion on the surface of the Bruxchecker was decreased (P<0.05). The scores of superficial and deep masseter, and the anterior portionof the temporalis were all significantly decreased (P<0.05). There was no significant change in the scores of the middle and posterior portions of the temporalis. Conclusion: The treatment by the low-frequency rTMS can reduce the incidence of bruxism and it is worthy of clinical application.

Key words: Sleep bruxism, Low-frequency repetitive transcranial magnetic stimulation, Bruxchecker