Effect of surface characterization and food colorants on color change, hardness, surface roughness, sorption and solubility and flexural strength of a resin for the manufacture of a total denture obtained by additive manufacturing (3D printing)

• Grant number: 24/22866-4
• 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: Cláudia Helena Lovato da Silva
• Grantee: Mariana Dâmaso de Simone
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

To obtain adequate aesthetics of the total dentures obtained by 3D printing, the characterization of the surface through the addition of resinous pigments is indicated. However, the literature remains scarce regarding the effects of these dyes on color, hardness, surface roughness, sorption, and solubility. Thus, the aim of this study is to evaluate a resin for complete denture obtained through additive manufacturing (3D printing) with extrinsic surface characterization, without characterization, and a conventional thermopolymerizable acrylic resin. The response variables will be color change, Knoop microhardness and surface roughness (n=120; ¿¿12 mm Ø x 3 mm thick), flexural strength (n=150, 65 x 10 x 3.3 mm), and sorption and solubility (n=120, 50 mm Ø x 0.5 mm thick). All variables will be evaluated immediately after specimen fabrication, and after 36 days of immersion in water (S1; n=10), coffee (S2; n=10), Coca-Cola (S3; n=10), or red wine (S4; n=10), simulating 3 years. Color will be assessed using the Standard Commission Internationale de L'Eclairage (CIE Lab) color system, recommended by the American Dental Association. Roughness will be evaluated using Laser Confocal Microscopy (Sa), while hardness, sorption, solubility, and flexural strength will follow the standards ANSI/ADA Specification No. 12 (1975), ISO 20795-1:2008, ABNT NBR ISO 4287:2002, respectively. The data will be evaluated for normality and homoscedasticity to define the statistical tests to be used, considering a 95% significance level (SPSS 22.0).