Renal cytotoxicity of endodontic materials' leachates

• Grant number: 24/07583-6
• Support Opportunities: Scholarships abroad - Research Internship - Master's degree
• Start date: February 01, 2025
• End date: July 31, 2025
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Marina Angélica Marciano da Silva
• Grantee: Brenda Fornazaro Moraes
• Supervisor: Debora Cristina Coraca-Huber
• Host Institution: Faculdade de Odontologia de Piracicaba (FOP). Universidade Estadual de Campinas (UNICAMP). Piracicaba , SP, Brazil
• Institution abroad: Medizinische Universität Innsbruck, Austria
• Associated to the scholarship: 23/09478-2 - In vivo analysis of the biological response, local and systemic migration of chemical elements released from calcium silicate-based materials in contact with connective and bone tissue, BP.MS

Abstract

Endodontic apical surgery is a procedure clinically performed after failed endodontic treatments or retreatments. This procedure usually involves the surgical exposure of the affected region, the removal of apical lesion by curettage, apicoectomy, root-end cavity filling using radio-opacified reparative materials aiming to obtain bone repair following this procedure. Different radio-opacifying compounds (bismuth oxide, tantalum oxide, calcium tungstate and zirconium oxide) are commercially used in reparative materials. Our research group previously reported the release of radio-opacifier from reparative materials locally (into dentine, subcutaneous and bone) and consequential systemic accumulation mainly in kidneys. The aim of this proposal is to investigate the cytotoxicity of materials' leachates over renal proximal epithelia cell line (NRK CRL-6509) in comparison with non-exposed cells. Materials characterisations will be performed using microscopy (SEM/EDS) and x-ray diffraction (XRD). For the cytotoxicity assays, the cells will be cultivated until confluence before plating (1 x 104) and exposed to the leachates obtained by materials samples immersed in culture medium (DMEM) for seven days. Cells will be analysed at days 4 (than exposed), 7 and 10 of culturing using trypan blue assay for live/dead cells. Additionally, cells will be lysed for RT-PCR comparative analysis between the reparative materials using previously validated markers for metal exposure metallothionein 1, 2A and 3 (designed using Primer-BLAST). Data obtained will be statistically analysed for normality and the appropriate statistical tests used for comparisons with a significance level of 5%.