Comparison of Effectiveness of the Bioadhesive Pastes Containing Licorice 5% and Topical Corticosteroid for the Treatment of Oral Lichen Planus: A Pilot Study

Background: Lichen planus is a chronic inflammatory mucocutaneous disease with immune systemʹs origin. There is no definite cure for that and present treatment methods are symptomatic. According the effects of topical medications and anti-inflammatory properties of licorice, this study is designed for comparison the effectiveness of the adhesives containing licorice with topical steroid on treatment of oral lichen planus. Materials and Methods: In this double-blind clinical trial, 40 patients randomly divided into two groups: licorice and topical corticosteroid therapy and were followed up for 12 weeks, we asked patients used the drugs four times in a day and after applying drugs avoid of eating, drinking and smoking for an hour. Data were analyzed by SPSS-19, using the independent samples t-test and Mann-Whitney U tests. Results: In this study the use of topical licorice as topical corticosteroids were effective in reducing pain, but the improvement of clinical signs was not effective as corticosteroids. The severities of lesion according Thongprasom classification were 1.2±1.03 in corticosteroid group and 2.6±0.9 in licorice group. There was a statistical significant difference between groups (p=0.006). Conclusion: Based on the findings of this study topical licorice 5% is not a good alternative for topical corticosteroids in the treatment of lichen planus.