Intracanal medications and gutta-percha with calcium hydroxide, biosilicate and associations. Evaluation of biological and antimicrobial properties

• Grant number: 24/16075-4
• Support Opportunities: Scholarships in Brazil - Master
• Start date: January 01, 2025
• End date: April 30, 2026
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Juliane Maria Guerreiro Tanomaru
• Grantee: Leonardo Ventura Barroti
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil
• Associated research grant: 23/13106-3 - Development of intracanal medications, gutta-percha and endodontic cement with tricalcium silicate, biosilicate and associations. Assessment of physicochemical, biological and antimicrobial properties, AP.R

Abstract

Biosilicate (BS, LaMaV/UFSCar, Brazil) is a glass-ceramic with the ability to promote osteogenesis and antimicrobial effect. Gutta-percha (GP) modified by biomaterials can favor the interface with bioceramic cements and bioactivity. This study is divided into 2 subprojects: Subproject 1: Aims to evaluate antimicrobial activity and biocompatibility by comparing different intracanal medications: (Part A) Bio-C Temp bioceramic medication (BCT, Angelus, Brazil); experimental calcium hydroxide paste (HCE): (HC + ZrO + PL); BCT associated with 50 and 75% HCE. (Part B) Experimental biosilicate paste (BS): BS + ZrO + PL; experimental calcium hydroxide paste HCE: HC + ZrO + PL; BS paste associated with 50 and 75% HCE. Subproject 2: The aim is to evaluate the bioactivity and biocompatibility of gutta percha (GP) modified by biosilicate using the methods of surface coating (DC, dip-coating) and (IN, incorporation) into GP. Antimicrobial activity (Subproject 1) will be evaluated using the Modified Direct Contact Test (MDCT) and bioactivity (Subproject 2) through surface analysis in Scanning Electron Microscopy (SEM). The biocompatibility (Subproject 1 and 2) of the different materials (intracanal medication and gutta percha) in the subcutaneous tissue of rats (n= 6/group/time period) will be assessed by implanting polyethylene tubes filled with the materials after 7, 15, 30 and 60 days. Sections of subcutaneous tissue will be stained with hematoxylin and eosin (H&E) to analyze the numerical density of inflammatory cells and the thickness of the capsules. Other sections adhered to silanized slides will be used for immunohistochemical reactions to detect interleukin-6 (IL-6), a mediator in the inflammatory response, and osteocalcin (OCN), a protein secreted by osteoblasts in the mineralization process. The Von Kossa method will be performed to identify possible birefringent structures in the capsule adjacent to the tubes. Analysis of results: The results will be analyzed and compared using specific statistical tests for each case and with a significance level of 5%.