Effect of different finishing protocols and intraoral polishes on flexural strength in dental ceramics: an in vitro study

• Grant number: 20/11063-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: December 01, 2020
• End date: May 31, 2022
• Field of knowledge: Health Sciences - Dentistry - Dental Clinics
• Principal Investigator: Wirley Goncalves Assuncao
• Grantee: Lillian Kerollyn Melcher de Souza
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

The objective of this work is to evaluate the influence of aging and different protocols for intraoral polishing and adjustment on surfaces of different ceramic materials (lithium disilicate (IPS e.max CAD - Ivoclar Vivadent®), nanoceramic resin (LAVA " Ultimate Restorative System - 3M ESPE) and zirconia (VITA In-Ceram® YZ, VITA) in their surface characteristics, roughness and flexural strength.The blocks of the materials will be cut to obtain four hundred and eighty specimens of size 16 x 3 x 1 mm, half of which of these will be aged in distilled water by means of thermocycling (5000 cycles), between 5 ° C and 55 ° C, every 10 seconds for 30 seconds. Four wear protocols will be analyzed: Wear with diamond tip mounted on a high rotation instrument with / without refrigeration and wear with diamond tip mounted on a multi-angle contra-angle instrument with / without refrigeration The polishing protocols analyzed will be: Manufacturer's instructions; Glaz and; with polishing; without polishing. All groups will have their surfaces analyzed using surface electron microscopy, roughness and mechanical resistance by the flexion test. The aged specimens and the control group will be submitted to the flexion test in a universal testing machine (EMIC) using the rupture module with a constant speed of 0.5 mm / min until the fracture is detected. Quantitative data will be collected and submitted to the normality curve to determine the most appropriate test followed by the indicated post-test, considering a 0.05 significance level.