HG-PROVOCATION OF ORAL-MUCOSA IN PATIENTS WITH ORAL LICHENOID LESIONS

Five amalgam-bearing patients, with clinically and histologically conf irmed oral lichenoid lesions, were tested by applying 0.5% Hg in petro latum for 10 min to clinically normal mucosa. Control sites were expos ed to petrolatum only. Four amalgam-bearing patients with no clinical evidence of oral lichenoid lesions served as controls; they were subje cted to similar Hg and petrolatum exposure. After 24 h, biopsies were taken and immunocytochemically analyzed with monoclonal antibodies to lymphoid and nonlymphoid cells. No distinct differences could be detec ted between the Hg-exposed areas of the lichen patients and those of t he nonlichen patients. Furthermore, normal mucosa exposed to petrolatu m only showed a staining pattern in the lichen patients which was no d ifferent from the nonlichen patients. The findings are discussed with respect to possible mechanisms of development of lichen-like lesions i n oral mucosa.