Association between central sensitization inventory and taste alterations in patients with burning mouth syndrome: a cross-sectional study

Abstract

Background: Burning mouth syndrome (BMS) is a chronic condition characterized by a burning sensation in the mouth without observable lesions, lasting over two hours daily for more than three months. In this study, we aimed to examine whether central sensitization inventory (CSI) scores differ between primary and secondary BMS (SBMS), arising from identifiable causes, and to explore their associations with taste thresholds and pain characteristics. Methods: This study was conducted between February 2022 and September 2025 and included 30 patients with BMS, 30 patients with SBMS, and 30 healthy controls. Taste assessments, including sweet, salty, sour, and bitter solutions and CSI evaluations, were performed. Statistical analyses, including correlation and comparison tests, were performed using the SPSS software. Results: Patients with BMS exhibited significantly larger pain visual analog scale (VAS) and CSI scores than those with SBMS. There were no significant differences in taste perception thresholds for the four flavors among the three groups. CSI scores showed significant positive correlations with taste thresholds for sweetness, saltiness, and bitterness in the BMS group, whereas no such correlations were observed in the SBMS group. The pain VAS scores in the BMS group were positively correlated with age and CSI scores. Receiver operating characteristic analysis revealed acceptable CSI discrimination for distinguishing BMS from SBMS (Area under the curve = 0.76). A cutoff of 27 yielded 70% sensitivity and 77% specificity, with an overall accuracy of 73%. Conclusions: Although no significant differences in taste thresholds were observed among the three groups, significant associations between the CSI scores and taste thresholds were identified exclusively in patients with BMS. While CSI scores do not directly assess central sensitization, they might reflect clinical features associated with central sensitization-related symptom burden in BMS, as observed for taste thresholds, pain intensity, and age. These findings suggest that taste alterations in BMS might be associated with central sensitization-related clinical features.