Oral Pathology and Oral Medicine
Oral Pathology and Oral Medicine tests the recognition, diagnosis and initial management of mucosal, salivary, odontogenic and osseous disease, plus the oral signs of systemic illness.
Core concepts
- Leukoplakia is a white patch that cannot be diagnosed as another disorder; it is a clinical term, not a histologic one. Erythroplakia has higher malignant transformation.
- Oral lichen planus shows bilateral white striae (Wickham striae) and a band-like lymphocytic infiltrate; malignant transformation is low but reported.
- Pemphigus vulgaris: IgG against desmoglein 1 and 3, intraepithelial clefting, positive Nikolsky sign, intercellular immunofluorescence.
- Mucous membrane pemphigoid: subepithelial separation, linear IgG and C3 at the basement membrane; gingival desquamation is common.
- Recurrent aphthous stomatitis: painful ulcers on non-keratinized mucosa, no vesicles.
- Odontogenic lesions: ameloblastoma in the posterior mandible, often multilocular; odontogenic keratocyst with parakeratin and satellite cysts.
- Squamous cell carcinoma: lateral tongue and floor of mouth; persistent ulcer, induration, fixation.
Worked example
A 55-year-old has desquamative gingivitis. Direct immunofluorescence is the key test. Intercellular IgG suggests pemphigus; linear basement membrane IgG and C3 suggests pemphigoid; a band-like T-cell infiltrate suggests lichen planus. Biopsy is not optional.
Traps
Do not label every white lesion leukoplakia before excluding frictional keratosis, candidiasis and lichen planus. Do not assume all radiolucencies are cysts. Do not miss systemic disease: diabetes, anemia, HIV and medications cause oral changes.