The Efficacy of Daily Prefrontal Repetitive Transcranial Magnetic Stimulation (rTMS) for Burning Mouth Syndrome (BMS): A Randomized Controlled Single-blind Study

Abstract

Background: Burning mouth syndrome (BMS) is a burning oral sensation without any corresponding abnormal findings. In some cases, BMS is refractory to pharmacologic treatments. Repetitive transcranial magnetic stimulation (rTMS) over left prefrontal cortex induces analgesic effect in both acute and chronic pain. However, its effect for BMS has not been evaluated.

Objective: The aim of this randomized, controlled, single-blind study was to assess the efficacy of prefrontal rTMS for BMS.

Method: Twenty patients with BMS were recruited and randomized to receive 30,000 pulses in total at 10 Hz TMS (n = 12) or sham TMS (n = 8). We assessed the change of BMS pain condition, functional status and mood until 2 months after the beginning of treatment.

Results: In the real group, the BMS pain intensity decreased 67%, and 75% of the patients reported >50% pain decrease on final assessment compared to baseline, without heavy side effects. There was significant pain reduction in subjects in the real group immediately after 1 week of treatment, whereas there was none in those in the sham group. Similar tendency was confirmed in change of functional status. Mood and the affective aspect of pain were not changed in this study.

Conclusion: BMS pain was significantly improved with 2 weeks of treatment of high frequency rTMS over left DLPFC compared to sham stimulation. Further study is needed to refine and improve TMS as a potential treatment of BMS.

Keywords: Burning mouth syndrome; Chronic pain; Left dorsolateral prefrontal cortex; Repetitive transcranial magnetic stimulation.