Cellular toxicity and EGCG action on simple and mixed biofilms of microorganisms of endodontic interest

• Grant number: 17/13061-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2017
• End date: August 31, 2018
• Field of knowledge: Health Sciences - Dentistry - Pediatric Dentistry
• Principal Investigator: Cristiane Duque
• Grantee: Thainara de Oliveira Assumpção
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

One of the main causes of failure in endodontic therapy is the persistence of microbial infection even after chemical-mechanical preparation and application of intracanal medication. Many authors have explored the use of herbal medicines in order to obtain new compounds that have therapeutic properties without causing microbial resistance. Among these are the flavonoids, natural phenolic compounds which have different properties such as antimicrobial, antioxidant, osteogenic and antiosteoclastogenic. One of these flavonoids that has received attention in the literature is epigallocatechin-3-gallate (EGCG), which has also shown effect against oral pathogens. Thus, the objectives of this study will be to evaluate the antimicrobial activity of EGCG on planktonic culture and simple or dual-species biofilms of microorganisms resistant to endodontic treatment, and to evaluate its toxicity on fibroblast culture. Tests will be performed in the planktonic culture to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of EGCG against Enterococcus faecalis, Pseudomonas aeruginosa, Actinomyces israelii, Streptococcus mutans and Fusobacterium nucleatum and also biofilm assays with all these microorganisms alone or combined with Enterococcus faecalis. In addition, the cytotoxicity of EGCG will be determined on L-929 fibroblast line after 24 h exposure using the MTT assay. The data will be analyzed in the statistical program, considering p <0.05. This work aims to contribute to the study of new biological alternatives for the elimination of persistent endodontic infection. (AU)