Study of the effect of gel formulations containing Sr2+ on dentin and bone mineralization in vivo

• Grant number: 21/08558-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: March 01, 2022
• End date: June 30, 2025
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Sandra Yasuyo Fukada Alves
• Grantee: Taíssa Cássia de Souza Furtado
• Host Institution: Faculdade de Ciências Farmacêuticas de Ribeirão Preto (FCFRP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Associated research grant: 19/08568-2 - Investigation of the extracellular vesicles (VEs) role in the initiation, propagation, regeneration, and modeling of biological mineralization, AP.TEM

Abstract

Dentin is a mineralized connective tissue that forms the inside of both the crown and the root of the tooth. It is composed of dentinal tubules that extend along the entire length of the tooth and are covered by enamel at the crown and cementum at the root. Considering the structure of dentin in the form of tubules and its communication with the dental pulp, an exposure of dentin leads to a reaction called Dentin Hypersensitivity (DH). HD can be defined as a short, sharp pain caused when the dentin is exposed, either by loss of enamel or by gingival recession, which makes the dentinal tubules permeable to both the oral cavity and the pulp. The aim of the present study will be to evaluate the potential of compounds containing Sr2+ in mineralization and occlusion of dentinal tubules, as well as in bone mineralization. 80 isogenic mice of the C57BL6 lineage will be used. The animals will be submitted to two experimental models: model of dentin exposure induced by isotonic solution (pH 2.3) and model of alveolar bone resorption induced by ligature. The animals will be treated topically with compounds containing Sr2+ in the form of a 10 wt% PVA gel in the region of the left molars where dentin exposure or in the ligation region (alveolar bone resorption region) will be evaluated. In this study we will test HAp nanoparticles in which Ca2+ will be replaced by Sr2+ and a compound formed by Flavonoid and Sr2+ (Morina-Sr2+). The animals of each experimental model will be divided into 5 experimental treatment groups: 1- PVA (Control); 2- PVA + HAp; 3- PVA + Ca90Sr10HAp; 4- PVA + SrAp; 5- PVA + morin-Sr2+. The gel will be kept in the region of application for 1 minute and applied daily for 3, 5 and 7 consecutive days, according to the experimental group. At the end of the treatment, the quality of the neoformed bone tissue will be analyzed by histomorphometry and by MicroCT; evaluation of inflammatory mediators in the region adjacent to the application of the gel, by qPCR and ELISA. We will evaluate the characteristics of dentinal tubules and quality of dentin formed by Scanning Electron Microscopy (SEM) and mapping of Ca, Sr and P elements. Infrared absorption spectroscopy (FTIR) and RAMAN will be used to assess the incorporation of Sr2+ in dentin. Analyzes by X-Ray Diffraction (XRD) will be used to evaluate the crystal structure of the tooth and the material deposited in the tooth. We will also evaluate the differentiation of odontoblasts after treatments with Sr2+ compounds. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

DE QUEIROZ, ALEXANDRA MUSSOLINO; BONILLA, CLAUDIA MARIA CARPIO; FURTADO, TAISSA CASSIA DE SOUZA; PALMA-DIBB, REGINA GUENKA; OLIVEIRA, HARLEY FRANCISCO DE; ARNEZ, MAYA FERNANDA MANFRIN; CARVALHO, FABRICIO KITAZONO DE; PAULA-SILVA, FRANCISCO WANDERLEY GARCIA. Acid challenge exacerbates activation of matrix metalloproteinases in permanent teeth undergoing radiotherapy. BRAZILIAN ORAL RESEARCH, v. 38, p. 9-pg., 2024-01-01. (21/08558-7, 10/17611-4)