At the end of the study 71% (groups A and B) of patients showed clinical remission or marked improvement. No improvement was noted in the control subjects (group C). These results were further confirmed by histological findings. There were no significant changes in laboratory values in the three groups. The acitretin concentration in plasma and tissue ranged from 0 to 50 mg with no difference between groups A and B, and it was very high in saliva (ranging from 4.9 to 43 mg) with higher concentrations in group A than in group B (due to a longer adhesion time in group A). Patients' compliance was excellent. The results show that mucoadhesive tablets of topical acitretin are efficacious in the treatment of oral leucoplakia without systemic side-effects.