Interaction between tobacco pigmentation, coffee and polishing processes on the roughness and optical characteristics of resin-based materials for CAD/CAM

• Grant number: 24/19565-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2025
• End date: February 28, 2026
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Aldiéris Alves Pesqueira
• Grantee: Laís Ribeiro Teles
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

According to the World Health Organization (WHO), around 1.3 billion people smoke globally; this habit is often associated with the consumption of erosive and pigmenting drinks, such as coffee, which increases the risk of color changes and, consequently, failures in dental restorations.Therefore, the general objective of this study will be to evaluate the interaction between pigmentation caused by cigarette smoke and coffee and polishing processes, analyzing their influence on the roughness and optical characteristics of different resin materials for CAD/CAM. The study will have four factors in analysis: (1) Resin materials for CAD/CAM, including RN (nanoceramic resin-Cerasmart) and ZS (zirconia and silica ceramics in an interpenetrating resin matrix-Shofu HC); (2) Surface treatments, which consist of OptraGloss/Ivoclar tip (POG) or palaseal surface sealant (Ps); (3) Aging (Ec+Ic): pigmentation process due to exposure to cigarette smoke (Ec) associated with immersion in coffee (Ic) and (4) analysis times at 2 levels: T0 - after 24 h of surface treatment and stored in distilled water at 37°C (baseline); and T1 - the specimens initially will be exposed to cigarette smoke and then immersed in coffee (Ec+Ic).After each cycle of one day of cigarette exposure (20 cigarettes), the specimens will be immersed in brewed coffee for 10 minutes. In total, 30 cycles (cigarette+coffee) will be carried out in order to simulate a period of 30 days of exposure to regular cigarette consumption associated with coffee. Two response variables will be considered: (1) surface characterization through roughness surface (Ra) and (2) optical analyzes through color change (¿E00), translucency (TP), contrast (CR). The quantitative 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%.