Physico-mechanical properties of conventionally and additively manufactured denture base resins subjected to different liquids and cleaners

• Grant number: 23/09808-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2023
• End date: October 31, 2024
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Andréa Cândido dos Reis
• Grantee: João Pedro Nunes Sessa
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

The main treatment method for edentulous patients is oral rehabilitation with complete dentures made of heat-cured. In parallel, the digital flow in dentistry is growing exponentially, which has made it possible to quickly make complete dentures through additive manufacturing. The cleaning of the resin with chemical solutions and the consumption of beverages by the patient, added to the roughness characteristics of the material, promote changes in physical-mechanical properties, such as discoloration, increased roughness and reduced microhardness. Thus, this study proposes the evaluation of physico-mechanical properties in complete denture bases made of heat-cured and printed resin submitted to different liquids and cleaners. The samples will be submitted to immersion in distilled water (control group), coffee and green tea solutions, and denture sanitizers: 1% sodium hypochlorite and effervescent tablet (Corega Tabs), simulating a 6-month exposure to liquids and denture cleaners. The color change will be determined before and after the immersion of the samples in the liquids and cleaners, by means of a portable spectrophotometer according to two evaluation systems of the International Commission of Eclairage (CIE): the CIE L*a*b* and the CIEDE2000. The surface roughness of the samples, before and after immersion in the liquids and cleaners, will be evaluated by means of a 3D Laser Confocal Microscope. The microhardness evaluation will be performed before and after immersion of the samples in the liquids and cleaners, using a Knoop-type microhardness meter. The data obtained will be evaluated for their distribution, and parametric or non-parametric tests will be applied depending on the distribution (p<0.05).