HEALING OF LICHENOID REACTIONS FOLLOWING REMOVAL OF AMALGAM - A CLINICAL FOLLOW-UP

174 patients referred to the Department of Oral and Maxillofacial Surgery, Central Hospital, Karlstad, Sweden during 1987 to 1989 for lichenoid lesions and evaluation of a possible connection with amalgam restorations were invited to a clinical re-examination. 159 of the patients were re-examined with the purpose of evaluating the long-term effect upon performed substitution therapy. Partial or total removal of amalgam had been recommended according to a set of given criteria. The re-examination showed that 62 patients had performed partial and 69 patients total removal of amalgam fillings. 28 patients had not performed any substitution therapy. There was a difference between recommended and performed therapy. The results demonstrated that 92% of patients with lichenoid lesions only in contact with amalgam fillings healed or improved clinically following removal of amalgam. No statistical difference was found in healing between patients who only removed fillings in contact and those who had removed all amalgam restorations. More than 60% of buccal lichenoid lesions without contact with amalgam at time of referral disappeared following amalgam substitution. Gingival lichenoid lesions did not respond to substitution of amalgam to another material. 3 out of 17 patch-tested patients demonstrated a hypersensitivity reaction to mercury. All lichenoid lesions in these patients healed following total substitution. Partial or total removal of amalgam fillings was also performed on 10 patients with completely negative patch-tests. 6 out of these patients demonstrated complete healing of their lichenoid reactions at re-examination. The lichenoid reaction is to be regarded as a reaction pattern within the oral mucosa directed towards a specific agens in patients predisposed to develop such a reaction. Dental amalgam plays an etiological role in the development of lichenoid reactions and should be removed when in clinical contact with the lichenoid lesion. Total removal of amalgam may also be tried in other cases in patients with long-standing atrophic or erosive lesions where other therapy forms have been tried with poor clinical result.