Mucoadhesive Herbal Gel Formulations For Canker Sores

Abstract

Canker sores, aphthous stomatitis or mouth ulcer is an ulcerative condition and a painful inflammatory process that is related to the oral mucosa which requires a combined treatment approach of both antimicrobial and wound healing processes. Cistus creticus L. and Inula viscosa (L.) Aiton have both various antimicrobial and antioxidant activities which are beneficial for antisepsis and wound healing. In this study, it was aimed to prepare and optimize mucoadhesive gels including hydroglyceric extracts of C. creticus and I. viscosa either alone or in combination using carboxymethyl cellulose and to evaluate gels by organoleptic, pH, viscosity, spreadability, texture, antimicrobial activity and cytotoxicity-cell proliferation controls. In the first step, the extracts of C. creticus and I. viscosa were analyzed by using LC-HRMS to determine phytoactive contents. Then, formulation optimization studies were carried out, and four different formulations were selected and evaluated in terms of organoleptic, pH, viscosity, spreadability and texture properties. They were found to be successful in terms of these examined parameters. The antimicrobial activities were tested by the microbroth dilution method and the minimum inhibitory concentrations, and results showed that while C. creticus provides antimicrobial efficacy, I. viscosa provides antiviral efficacy for the formulas related to dose- dependent activities against all studied mouth pathogens. Cell proliferation and cytotoxicity test results showed that the most cytotoxic formulation was the one that included C. creticus extract alone while the lowest cytotoxic one was the one that included I. viscosa extract alone, against gingival fibroblast cells. As a conclusion, the formula included 32% combination of hydroglyceric extracts of C. creticus and I. viscosa (1:1) presented antimicrobial and antiviral efficacy with acceptable cytotoxicity, which was found to be encouraging for further studies.