Effect of phyllanthus amarus coating denture resin on candida adhesion and its effect on human gingival fibroblast

Abstract

© 2020 Trans Tech Publications Ltd, Switzerland. Candida infection has become increasingly important as an opportunistic infection frequently found in the oral cavity of denture wearing patients. The infection develops on oral mucous membrane and can spread to other parts of the body. Phyllanthus amarus, extensively grown in many tropical and subtropical countries, has been reported to have various medicinal properties including antimicrobial activity. This study aimed to assess the effect of P. amarus coating denture resin on Candida adhesion and its effect on human gingival fibroblast. The P. amarus coating solution was prepared by water extraction of dried leaves and freeze drying. Denture PMMA resin (SCG Chemical, Thailand) samples were made and coated with various concentrations (0.01-10 mg/mL) of P. amarus solution. Candida adhesion assay was performed on C. albicans ATCC 10231, C. glabrata ATCC 6258, C. krusei ATCC 90030 and C. tropicalis ATCC 13803 based on the method described by Samaranayake and MacFarlane. Cytotoxicity test was done on human gingival fibroblasts (HGF) according to ISO standard 10993-5/2009 for medical product testing. The result showed that P. amarus coating denture resin exhibited an inhibitory effect on the adhesion of all species of test Candida. Cytotoxicity testing revealed a dose-dependent effect of the P. amarus extract on human gingival fibroblast. At the concentrations of 0.1, 1, 5 and 10 mg/mL, the extract produced 84.7%, 73.4%, 64.7% and 38.2% of cell viability, respectively. In conclusion, coating denture resin with P. amarus at a concentration of 1 mg/mL can be used safely as a natural alternative preventive to control or prevent Candida infection caused by C. krusei and C. tropicalis in denture-wearing patients avoiding side effects of chemical antifungal agents. Further studies are needed to define the antifungal components and mechanisms of action as well as clinical trials in the patients.