CLINICAL AND LABORATORY INVESTIGATIONS DOI 10.1111/j.1365-2133.2005.06490.x Silver nitrate cautery in aphthous stomatitis: a randomized controlled trial M.R. Alidaee, A. Taheri, P. Mansoori and S.Z. Ghodsi Department of Dermatology, Razi Hospital, Tehran University of Medical Sciences, Vahdat Eslami Street, Tehran, Iran Correspondence Arash Taheri. E-mail: shtaheri@sina.tums.ac.ir Accepted for publication 4 October 2004 Key words: aphthous stomatitis, cautery, pain, randomized controlled trial, silver nitrate Conflicts of interest: None declared. Summary Background Aphthous stomatitis is a painful, recurrent disease of the oral mucous membrane. Silver nitrate sticks have been used for a long time to provide pain relief for the duration of an aphthous ulceration, with only one application. Sil- ver nitrate causes chemical cauterization and increases the depth of injury. Objectives To study the effect of chemical cautery with silver nitrate in reducing pain of aphthous ulceration and to determine if this treatment shortens or pro- longs healing. Methods In a randomized, patient-blinded, placebo-controlled study, 97 patients with painful minor oral aphthous ulceration were randomized to receive silver nitrate cautery or placebo. The severity of pain was rated on a three-category scale (severe, mild, none) and was recorded each day until the seventh day after the procedure. The lesion size was recorded at the time of the procedure and on the seventh day afterwards. In the treatment group, the ulcer was gently painted with a silver nitrate stick until it turned white. In the placebo group, the ulcer was gently painted with a placebo stick. Results In the treatment group, 33 of 47 patients (70%) evaluated and in the pla- cebo group, four of 38 patients (11%) evaluated had reduction in severity of pain 1 day after the procedure. The difference was statistically significant (P <0Æ001). On the seventh day after the procedure, the ulcers were completely re-epithelialized in 39 patients (83%) in the treatment group and in 34 patients (89%) in the placebo group. The difference was not statistically significant (P ¼ 0Æ39). Conclusions The results of our study showed that one application of silver nitrate can decrease the severity of pain in aphthous ulceration without significantly shortening or prolonging healing time. We did not observe any side-effects in our study. The effect is rapid and lasts for the duration of the lesion. The treat- ment is simple and cost-effective in patients with infrequent recurrences. Aphthous stomatitis is a painful, recurrent disease of the oral mucous membrane. The name comes from a Greek word, aphtha, for ulcer. It begins as small, red, discrete or grouped papules, which in a few hours become necrotizing ulcers. Oral aphthae are sharply circumscribed necrotic ulcers with a grey fibrinous exudate and an erythematous halo. Aphthous ulceration can be classified into three differ- ent types: minor, major and herpetiform. 1 Minor aphthae are generally located on nonkeratinized, labial or buccal mucosa, the soft palate and the floor of the mouth. They can be singular or multiple, and tend to be small (less than 1 cm in diameter) and shallow. They heal spontaneously within 7–10 days. Major aphthae are larger and cause deep- er ulcers. Major aphthae may also be more likely to scar. Herpetiform aphthae are multiple, clustered, 1–3-mm lesions that may coalesce into larger ulcers. The aetiology and pathophysiology of aphthous stomatitis remain incompletely understood. The primary disorder appears to be the result of activation of the cell-mediated immune system. 2–4 Light microscopic histopathology is non- specific. Pre-ulcerative lesions exhibit a spongiotic epidermis with basal cell damage infiltrated by lymphocytes and poly- morphonuclear leucocytes. A superficial dermal mononuclear inflammatory infiltrate is accompanied by the appearance of polymorphonuclear leucocytes beneath the ulcer. 5 For their size, aphthous ulcers are disproportionately pain- ful. The pain tends to subside after 4–5 days, but during this period it can interfere with eating. Usually, no treatment is Ó 2005 British Association of Dermatologists • British Journal of Dermatology 2005 153, pp521–525 521