Burning mouth syndrome Burning mouth syndrome (BMS) is a chronic, complex condition characterised by a persistent burning or scalding pain in an intraoral cavity that appears clinically normal . Because BMS is essentially a diagnosis of exclusion, clinicians must thoroughly investigate and rule out local, systemic, and psychological factors. [ 1 , 2 , 3 ] Causes and Classification of BMS BMS is classified into two distinct forms based on its underlying origin: 1. Primary (Idiopathic) BMS When a thorough clinical evaluation, laboratory panel, and imaging show no identifiable local or systemic cause , the condition is termed primary BMS. Current research strongly indicates that primary BMS is a neuropathic pain condition . [ 1 , 2 , 3 ] Small Fiber Neuropathy: Degeneration or loss of peripheral thermal and pain nerve fibers in the oral mucosa. Trigeminal and Chorda Tympani Dysregulation: Alterations in sensory and taste pathways that cause the brain to incorrectly regist...