The significance of a positive patch test to mercury in oral disease

Contact sensitivity to menthol and peppermint in patients with intra-oral symptoms

We report 12 cases of contact sensitivity to the flavouring agents menthol and peppermint oil in patients presenting with intra-oral symptoms in association with burning mouth syndrome, recurrent oral ulceration or a lichenoid reaction. The patients were referred from the Glasgow Dental Hospital over a 4-year period for assessment of the possible contribution of contact sensitivity to their complaints. 5 patients with burning mouth syndrome demonstrated contact sensitivity to menthol and/or peppermint, with 1 patient sensitive to both agents, 3 positive to menthol only and 1 to peppermint only. 4 cases with recurrent intra-oral ulceration were sensitive to both menthol and peppermint. 3 patients with an oral lichenoid reaction were positive to menthol on patch testing, with 2 also sensitive to peppermint. 9 of the 12 cases demonstrated additional positive patch test results. After a mean follow-up of 32.7 months (range 9-48 months), of the 9 patients that could be contacted, 6 patients described clearance or improvement of their symptoms as a consequence of avoidance of menthol/peppermint.

Resolution of oral lichenoid lesions after replacement of amalgam restorations in patients allergic to mercury compounds

The significance of contact allergy in patients with various oral symptoms was studied. Positive patch-test reactions to mercury compounds were found in 21/91 patients. Of these, 18 had lichenoid lesions in oral mucosa in close contact to amalgam fillings, and three patients with contact allergy had neither amalgam fillings in their teeth nor visible oral lesions. Amalgam replacement was carried out in 15/18 symptomatic patients. The fillings were replaced with gold in three cases, composite resin fillings in six, glass ionomer in three and both gold and composite materials in three cases. In 10 patients there was complete replacement and in five it was restricted to the fillings adjacent to the mucosal lesions. After a mean follow-up period of 3.2 years a complete cure was seen in seven patients, each of whom had had all their fillings changed. A marked improvement occurred in six patients, and there was no change in two.