Color Stability of Denture Base and Relining Materials After Thermocycle


Kansu G., Terzi Ü. T. , Ağan H. , İnan G.

International Association for Dental Research (IADR), Barcelona, Spain, 14 - 17 July 2010, pp.797

  • Publication Type: Conference Paper / Summary Text
  • City: Barcelona
  • Country: Spain
  • Page Numbers: pp.797

Abstract

Color Stability of Denture Base and Relining Materials After Thermocycle

OBJECTIVE: The aesthetic requirement provided by optical properties is of paramount importance for all dental applications. Color stability refers to the ability of a material to maintain its reflectance and reflected wavelength. Discoloration of autopolymerizing resins and nylon polimers may lead dissatisfaction. The purpose of this study was to evaluate the effect of thermocycle process that is a way to predict long term durability on two relining material, a thermoplastic nylon denture base material and an autopolymerizing acrylic denture base material by using colorimeter.

METHOD: Ten disc shaped specimen (10 mm diameter, 2 mm thickness) were prepared by using two autopolymerizing relining materials; UfiGel Hard (UGH), Truliner (T), a thermoplastic nylon; Flexiplast (FP) and an autopolymerizing acrylic; QC 20 (QC) according to the manufacturer's recommendations. Total of forty specimens were subjected to thermocycling for 4000-12000 cycles between 5-55° C in water. Color measurements were made immediately after deflasking and thermocycling processes (4000-12000). Color changes (ÄE) were calculated by using colorimeter. To assess the effect of material type and cycling period on ÄE values, a two-way analysis of variance (ANOVA) is carried out followed by the Fisher's LSD test (á=0.05).

RESULTS: Statistical analysis revealed that material type and cycling period has significant effect on ÄE values. It is seen that while UGH displays largest changes in ÄE values compared to the other materials, FP and QC exhibits the smallest changes in ÄE values. Furthermore, the difference between the ÄE values of FP and QC exhibits is found statistically no significant, which means that two material performances are nearly the same in terms of ÄE values.

CONCLUSION: Within the limitations of this study, denture base materials showed better tolerance to the thermocyling process than relining materials, but all demonstrated clinically acceptable color stability values.