Oral and Maxillofacial Medicine and Mucosal Disease
Core Concepts
Mucosal disease diagnosis rests on lesion morphology, duration, and systemic associations. Master the classification of white lesions (leukoplakia, lichen planus, frictional keratosis, chronic hyperplastic candidiasis, hairy leukoplakia), red lesions (erythroplakia, erythroleukoplakia), and ulcerative conditions (aphthous, herpes, pemphigus, mucous membrane pemphigoid, drug reactions). Understand the malignant transformation risk of oral potentially malignant disorders and when to biopsy.
Common Traps
- Calling any white patch leukoplakia without excluding frictional keratosis and candidiasis first.
- Missing erythroplakia as the highest-risk lesion despite its subtle appearance.
- Confusing recurrent aphthous stomatitis with herpes (aphthae are non-vesicular, intraoral, and recurrent in the same pattern).
- Overlooking drug-induced lichenoid reactions and graft-versus-host disease in patients on multiple medications or post-transplant.
Rule of Thumb
Biopsy any oral lesion that persists beyond two weeks after removing an identifiable cause, and always biopsy erythroplakia and indurated or nonhealing ulcers. A worked example: a 60-year-old with a painless red patch on the floor of the mouth - do not observe; incisional biopsy is indicated because erythroplakia carries the highest transformation risk. Use direct immunofluorescence for suspected autoimmune blistering (linear IgG/C3 at basement membrane in pemphigoid; intercellular in pemphigus).
Management Pearl
Document tobacco and alcohol exposure, and coordinate with dermatology or internal medicine when mucocutaneous findings suggest a systemic disease.