Physicochemical and biological characteristics of clinker with different particle sizes besides root repair cements and root canal sealers based on calcium silicate

• Grant number: 20/11011-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): November 01, 2021
• Effective date (End): February 29, 2024
• Field of knowledge: Health Sciences - Dentistry - Endodontics
• Principal Investigator: Mario Tanomaru Filho
• Grantee: Karina Ines Medina Carita Tavares
• Host Institution: Faculdade de Odontologia (FOAr). Universidade Estadual Paulista (UNESP). Campus de Araraquara. Araraquara , SP, Brazil

Abstract

The bioceramic materials of Angelus are handled from the clinker, manufactured with different particle sizes. The aim of this study will be to evaluate the morphological, physicochemical and biological properties of clinker with different particle sizes (2 to 30 µm or less than 2 µm) and the new root repair cements (Bio-C Repair and Bio-C Pulpo) and root canal sealers (Bio-C Sealer) based on calcium silicate. MTA, MTA Repair HP, Biodentine and AH Plus will be used for comparison. Subproject 1: Evaluation of clinker regarding particle size effect (< 2 µm and between 2 to 30 µm), liquid (distilled water or liquid with additives) and radiopacifier (calcium tungstate), compared to MTA and MTA Repair HP. The materials will be characterized by DRX, SEM and EDS. Setting time, radiopacity and pH will be analyzed according to ISO 6876. Solubility will be evaluated by the percentage of mass loss after immersion of materials in distilled water, PBS or DMEM. The biological properties will be evaluated by tests of cell viability and bioactivity. Other methodologies can be developed according to initial results through a partnership with the University of Birmingham, Birmingham, United Kingdom. Subproject 2: To evaluate by micro-CT (9 µm) using bovine teeth, the pH effect on the dentine/material interface, porosity and volumetric change, in addition to the analysis by SEM of bioactivity and material/dentin interface of the clinker < 2 µm and between 2 to 30 µm manipulated with water and liquid with additives, associated to the radiopacifier zirconium oxide after immersion in butyric acid (pH 4.5) or PBS (pH 7.0) for different periods, in comparison with Bio-C Pulpo and Biodentine. Subproject 3: To evaluate by micro-CT using circular and flattened root canals, the pH effect and sealer thickness on the gutta-percha/sealer /dentine interface, volumetric change and the presence of voids of Bio-C Sealer or AH Plus, before and after immersion in butyric acid or PBS for different periods. The bioactivity, as well as gutta-percha/sealer /dentine interface of the materials will also be analyzed in SEM. Subproject 4: To analyze by micro-CT, the pH effect on volumetric change and porosity of root-end cavities after filling with Bio-C Repair, MTA Repair HP and Biodentine, before and after immersion in butyric acid or PBS for 7 days. The data will be submitted to the appropriate statistical tests (± = 0.05). (AU)