Local and systemic effects of different radiopacifiers released from calcium silicate-based materials.

• Grant number: 25/03728-2
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: April 01, 2025
• End date: March 31, 2028
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Marina Angélica Marciano da Silva
• Grantee: Jennifer Santos Pereira
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil
• Associated research grant: 22/03093-9 - Local and systemic effects of radiopacifiers from reparative dental materials, AP.PNGP.PI

Abstract

The objective of this study is to evaluate the local and systemic biological responses to the interaction of connective and bone tissue with calcium silicate-based materials containing different radiopacifiers. The following materials will be assessed: Gray-MTAFlow (bismuth oxide), White MTAFlow (tantalum oxide), MTA Repair HP (calcium tungstate), Biodentine (zirconium oxide), and tricalcium silicate (positive control - without radiopacifier). Direct and indirect contact analyses will be conducted using primary cell cultures (fibroblasts and bone marrow cells) and cell lines (3T3 fibroblasts from mice and NRK cells derived from proximal renal epithelium). In primary cell culture analysis, cells will be maintained with periodic medium changes and evaluated under direct contact with the materials for up to 14 days, considering degradation effects, medium pH, leachates, live/dead cell count, and molecular expressions of alkaline phosphatase, osteocalcin, osteopontin, sialophosphoprotein, transforming growth factor-ß (TGF-ß), bone sialoprotein, collagen 1-a, and different isoforms of metallothionein. RNA samples collected by lysis will be converted into complementary DNA (cDNA) and adjusted to the expression of glyceraldehyde 3-phosphate dehydrogenase (GAPDH), serving as an internal control for reverse transcription polymerase chain reaction (RT-PCR). For indirect contact tests, leachates obtained from the immersion of tested material samples in sterile cell culture medium (sDMEM) will be applied to the cell cultures. On day 14, the same molecular expressions will be analyzed by RT-PCR and compared to the direct contact results. For cell line cultures, the same experimental conditions described for indirect contact tests will be applied. Data distribution will be verified using the D'Agostino and Pearson test. A significance level of 5% will be considered for all analyses.