Gingival pigmentation as the sole presenting sign of chronic lead poisoning in a mentally retarded adult.

A diagnosis of chronic lead poisoning in a mentally retarded adult with pica was initially proposed because of the presence of a "lead line" on the patient's gingiva. The patient had no other signs or symptoms suggestive of her toxic state. Lead poisoning is reviewed from the standpoint of epidemiology, pathophysiology, clinical and oral manifestations, and diagnostic procedures. Dentists working with children or mentally retarded patients should be aware of the increased incidence of lead poisoning in these patient populations and the importance of oral findings and lead-screening techniques in the detection of lead poisoning.