Effect of acid erosion in situ on the structural and optical characteristics of nanoparticulated bis-acrylic composite resin, unpolished and polished with different surface treatments

• Grant number: 21/08186-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: September 01, 2021
• End date: August 31, 2022
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Aldiéris Alves Pesqueira
• Grantee: Thiago Scudeler Foltran
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

The purpose of this study will be to evaluate the influence of acid erosion in situ on the structural and optical characteristics of nanoparticulated bis-acrylic composite resin, unpolished (gauze with alcohol) and polished with different surface treatments (silicone rubber tip containing silicon carbide particles - Astropol Polishing Kit - Ivoclar Vivadent) and 02 surface sealants (Biscover LV - Bisco e Palaseal - Kulzer), analyzing surface roughness (Ra), Knoop Hardness (KH), color change (”E00, ”L, ”C, ”H), translucency (TP) and contrast (CR). Eighty specimens will be manufactured in dimensions of 5×5×1,5 mm, these will be divided into groups (n=10) according to surface treatments and in situ experiment (with and without acid erosion). This surface treatments will be performed: NP - unpolished (gauze with alcohol); PA - polishing with Astropol kit (Ivoclar); SB - surface sealant Biscover LV (Bisco) e SP - surface sealant Palaseal (kulzer). For the in situ experiment will be selected 10 volunteers, each volunteer will use an intraoral appliance containing eight specimens (two specimens per experimental group), and only one specimen from each experimental group will be subjected to the acid erosion process. The acid erosion consisted of rinsing with 150 ml of a recently opened cola beverage (Coke, pH = 2.3) 4 x 5 min/day (8AM, 12PM, 4PM and 8PM) for 14 consecutive days. After each erosive challenge, the volunteers will rinse the appliance with distilled water for 10s and return it into the mouth. The analysis will be performed after the surface treatments (T1) and after in situ experiment (T2). The data obtained in each analysis will be submitted to the normality test and later to the most appropriate statistical test, with a 5% significance level. (AU)