Protective effect of periodic intraoral polishing on the roughness and optical characteristics of resin materials for cad/cam after brushing cycles associated with immersion in staining solutions.

• Grant number: 24/14680-8
• Support Opportunities: Scholarships in Brazil - Master
• Start date: July 01, 2025
• End date: April 30, 2026
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Aldiéris Alves Pesqueira
• Grantee: Mariana Nogueira Bianchi
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

It is essential to evaluate the impact of different forms of aging on the optical properties and durability of prosthetic crowns made of resin materials for CAD/CAM, as well as to understand how periodic repolishing contributes to preserving surface quality, minimizing degradation and pigmentation. Thus, the general objective of this study will be to evaluate the protective effect of periodic intraoral repolishing on the roughness and optical characteristics of two resin materials for CAD/CAM: zirconia and silica ceramic in an interpenetrating matrix of Shofu HC resin (SHOFU DENTAL) and the Tetric CAD nanohybrid resin block (IVOCAR), both with surface treatment with a diamond-coated silicone tip (OptraGloss-IVOCLAR) and subjected to different simulated brushing (ES) cycles associated with immersion (I) in acid and dye solutions (ES+IAD-distilled water, ES+ICP-black tea and ES+IVT-red wine). Different simulated brushing (ES) cycles will be performed to simulate different years of daily brushing: 10,000 cycles (equivalent to 1 year), 30,000 cycles (equivalent to 3 years) and 50,000 cycles (equivalent to 5 years). After each simulated brushing cycle, the specimens will be immersed in different acid and dye solutions (ES+I). They will be exposed to three different solutions: distilled water (ES+IAD), black tea (ES +ICP) and red wine (ES +IVT). At each cycle representing 1 year of simulated clinical use of the restoration ((ES) of 10,000 cycles + (I) 12 days of immersion) the specimens belonging to the "clinical repolishing" groups will undergo repolishing (RPC), until completing 5 years of simulation. The analyses will be performed at 3 levels: (T0 = initial reading) after storage in distilled water at 37°C for 24 hours; (T1) after ES+I (3 years) and (T2) after ES+I (5 years). The data obtained in each analysis will be subjected to the normality test and subsequently to the most appropriate statistical test, with a significance level of 5%.