Identification of components of the extracellular matrix of Streptococcus mutans on the surface of different 3D printing resins for occlusal splints

• Grant number: 24/19155-9
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: January 21, 2025
• End date: March 20, 2025
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Ana Paula Macedo
• Grantee: Sarah Ribeiro Cruz Araújo
• Supervisor: Wanessa de Cassia Martins Antunes de Melo
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil
• Institution abroad: Center For Physical Sciences And Technology, Lithuania
• Associated to the scholarship: 23/05068-4 - Analysis of physical and mechanical properties before and after thermocycling of printed resins used for making occlusal splints., BP.IC

Abstract

Occlusal splints, commonly used in the treatment of Temporomandibular Disorders (TMDs) and Bruxism, are traditionally made from conventional acrylic resin. However, recent advances in CAD-CAM technology have introduced 3D printing as a promising alternative, resulting in fewer clinical steps and predictable outcomes. Despite their growing use, concerns have emerged regarding the surface roughness of 3D-printed materials and the potential for increased biofilm formation, particularly the biofilm formed by Streptococcus mutans, a key contributor to cavities and gingivitis. The extracellular matrix (ECM) produced by these microorganisms, provides greater integrity and cohesiveness, and serves as a protective barrier, complicating the clinical control of pathogenic biofilm. composition of the ECM, which includes extracelular DNA (eDNA), varies based on the microbial species and environmental conditions, making it an important focus in dental research. Despite the relevance of this topic, there is limited literature on the interaction between biofilm formation and 3D printing resins used for occlusal splints. his research project aims to analyze and compare the formation of colonies of S. mutans and its extracellular matrices on the surface of 3D printing resins - Smart Print Bio Bite Splint Clear - Smart Dent®, Cosmos Splint - Yller®, and SS Splint - Printax® - with the conventional thermopolymerizable acrylic resin (Clássico Artigos Odontológicos Clássico Ltda). To conduct this study, circular specimens will be prepared, consisting of 81 printed samples and 27 conventional acrylic samples (n = 9; Ø20 mm x 3 mm). After standardized finishing and polishing, surface roughness (Sa) of all samples will be evaluated. The extraction of extracellular polymeric substances (EPS) from S. mutans biofilm will be performed, along with quantification of polysaccharides and total proteins from the EPS, as well as the extraction and quantification of eDNA The data obtained from these experiments will be statistically assessed to determine the normal distribution (using Shapiro-Wilk test) and homogeneity of variances (using Levene's Test). Depending on the results, an appropriate statistical model will be applied, with a significance level of 5%.