Burning Mouth Syndrome 2026: From “Diagnosis of Exclusion” to a Structured Diagnostic Algorithm (Narrative Review)

Burning mouth syndrome remains a frequent source of diagnostic delay, repeated consultations, and fragmented care because it has long been treated as a "diagnosis of exclusion."Recent updates in orofacial pain classification and research diagnostic frameworks support a practical shift: from an exclusionary label toward a structured diagnostic algorithm and staged, phenotype-guided management.This narrative, algorithm-focused clinical review aims to summarize clinically actionable evidence and to propose a "minimum sufficient workup" that prioritizes safety, efficiency, and patient-centered communication.We first outline pragmatic diagnostic criteria and key symptom patterns, then integrate current concepts of mixed mechanisms-peripheral neuropathic features, central/nociplastic amplification, and psychosocial modulators-that account for symptom fluctuation and discordance between symptom severity and objective findings.The core of this review is a one-page stepwise algorithm: (1) confirm chronicity and absence of visible mucosal disease, (2) screen for red flags requiring urgent evaluation, (3) address common local contributors (e.g., candidiasis, irritants, contact allergy, xerostomia), (4) perform a targeted systemic/medication/deficiency panel, and (5) phenotype patients to guide staged treatment choices and follow-up.Finally, we provide a practical management framework emphasizing education, trigger control, and individualized combinations of topical, systemic, and behavioral interventions with predefined reassessment intervals.Future priorities include phenotype-stratified randomized trials and implementation outcomes that quantify reductions in diagnostic delay, misdiagnosis, and unnecessary testing.