Oral lichenoid reaction associated with tin component of amalgam restorations: a case report.

Amalgam or its components may cause type IV hypersensitivity reactions on the oral mucosa. Majority of the reported cases involved a delayed hypersensitivity to mercury. A case of bilateral oral lichenoid reaction is presented, which was present in relation to amalgam restorations. Histopathological features were compatible with lichenoid mucositis. Patch test was positive with pulverized amalgam and tin. The lesion healed up after replacement of restorations with an intermediate restorative material. The clinician should be aware of all possible pathological etiologies of white lesions. If there is any doubt about the nature or management of an unusual oral lesion, referral to appropriate specialists is mandatory.