The effects of topical anesthesia on oral burning in burning mouth syndrome.

Burning mouth syndrome (BMS) is an oral pain disorder of uncertain origin. Central or peripheral pain mechanisms may play a role in the oral burning of BMS. We tested the effect of a topical anesthetic (dyclonine HCl) on patients' intensity ratings for oral burning, taste dysgeusia and the taste of two chemical stimuli (1.0 M NaCl and 1.0 M sucrose). A total of 33 patients (9 male and 24 female, average age: 60 yr) are included in this analysis. The anesthetic reduced the perceptual intensity of both chemicals in these patients on four out of five postanesthesia trials (p < 0.01). The BMS cohort included 12 patients whose burning increased (p < 0.001), 14 patients whose burning did not change, and 7 patients whose burning decreased (p < 0.001) after anesthesia. Baseline dysgeusias (n = 13) decreased in intensity (p < 0.001) after anesthesia, suggesting BMS dysgeusia is related to the activation of peripheral taste mechanisms. The results also suggest that BMS oral burning may be a disorder of peripheral pain pathways in some patients.