The aim of the study was to determine, in a group of patients with 
therapy-resistant burning mouth syndrome (BMS), the possible deficiency of 
vitamins B1, B2, and B6 and the effect of proper vitamin replacement therapy. 
Sixteen individuals, aged 47 to 81 years, participated in the study. All 
underwent a base-line examination comprising anamnestic information, subjective 
assessment of symptoms, dietary registration, salivary analysis, and serum 
analysis of thiamine (B1), riboflavine (B2), and pyridoxine (B6). Fifteen 
individuals had low thiamine and/or riboflavine levels in accordance with 
suggested levels in the literature and were given replacement therapy. No effect 
on BMS of vitamin replacement therapy or placebo therapy could be demonstrated.