Thermal cycling effect and disinfection on the microhardness stability of color of acrylic resins for denture base

• Grant number: 09/16971-0
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: May 01, 2010
• End date: December 31, 2010
• Field of knowledge: Health Sciences - Dentistry - Dental Materials
• Principal Investigator: Marcelo Coelho Goiato
• Grantee: Gabriella Trunckle Baptista
• Host Institution: Faculdade de Odontologia (FOA). Universidade Estadual Paulista (UNESP). Campus de Araçatuba. Araçatuba , SP, Brazil

Abstract

The hygiene care of dentures and oral mucous tissue in edentulous has a great importance in both the general health and the social intimacy. However, physical qualities such as the color and the microhardness of the acrylic resins of dentures can be altered through either its continuous use or the disinfection methods. Thus, the purpose of this work is to assert the influence of the thermal cycling and the disinfection on the color stability and microhardness of acrylic resins used in dentures. Four different types of acrylic resins will be evaluated: Onda Cryl, QC 20, Classic and Lucitone. Each resin will be divided into 4 groups (n=7). Each group will be submitted to a type of disinfection (efferdent, hypochlorite 1%, chlorhexidine 4%; microwave energy). After the polymerization, all the samples will be submitted to thermal cycling for 1,000 cycles, with 60-second alternating baths between 5±1°C e 55±1°C. After this period the samples will be stored and disinfected for 60 days, when a new thermal cycling procedure for 1,000 will be carried out. The microhardness will be measured through a microdurometer and the color reading will be done by a spectrophotometer, using the CIE L*a*b* system. The color reading and the microhardness measurement will be carried out in the initial period and after each thermal cycling and disinfection period. The obtained data will be submitted to analysis of variance (ANOVA), in order to verify the existence of differences among the variables in study and in case a difference is recognized, an appropriate test will be applied to identify the group in which the difference occurred.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

GOIATO, MARCELO C.; DOS SANTOS, DANIELA M.; BAPTISTA, GABRIELLA T.; MORENO, AMALIA; ANDREOTTI, AGDA M.; BANNWART, LISIANE C.; DEKON, STEFAN F. C.. Effect of thermal cycling and disinfection on colour stability of denture base acrylic resin. GERODONTOLOGY, v. 30, n. 4, p. 276-282, DEC 2013. (09/16971-0)