Contemporary provisional restorations: effect of time and immersion solutions in physic mechanic properties

• Grant number: 16/19952-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2017
• End date: December 31, 2017
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Aldiéris Alves Pesqueira
• Grantee: Caroline de Freitas Jorge
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

The materials used to confection of the provisional restorations are submitted to a moist oral environment and subjected to hygroscopic and hydrolytic effects in different levels, that depend of the polymeric chemical and structure, that influence in mechanic and chemical properties. Recently, the pre-fabricated polymer blocks or high density polymer to CAD/CAM system came as an excellent choice to confection of provisional restorations, however, the physic-mechanic behavior in compare to other materials used to confection of temporary restorations is limited in literature. This way, the objective of this present study is to evaluate sorption (SR), solubility (SO) surface roughness (Ra) and Knoop micro hardness (MK) of different kind of resin used to provisional restoration confection, after different immersion periods in acid/stain solutions. There will be made 160 specimens with 10×10×3 (±0,005mm), divided in 16 groups (n=10) according the material and solution. Four different resin will be evaluated: RAT - thermo polymerized acrylic resin (Clássico), RAA - auto polymerized acrylic resin (Alike), RB - nanoparticulate bisacrylic resin (Protemp4) and RCAD - pre-fabricated polymer blocks (PMMA) to CAD/CAM system (Telio CAD); immersed in following solutions: artificial saliva (S- Control), cola soft drink (R), coffee (C) and wine (V), and after different immersion periods (7, 14, 28, 90 e 180 days). The measurements of SR, SO, Ra and MK will be carry out before and after each immersion period. To the SR and SO analyses, the specimens will be submitted to drying test, according to #12 American Dental Association (ADA) specification. The values of Ra (arithmetic average) will be measured through portable perfilometer rugosimeter. To MK analyses, the specimens will be measured in microhardness equipment. The data will be analyzed the adherence testing curve, applying the appropriate statistical test to compare the specimens' average values. (AU)