COLOR STABILITY OF THREE PROVISIONAL MATERIALS AFTER EXPOSURE TO TWO CHROMATOGENS BEFORE AND AFTER THERMOCYCLING – AN IN VITRO STUDY

Abstract

Aim - The present investigation was done with an aim to evaluate and compare the effect of two chromatogens on color stability of three provisional materials before and after thermocycling. Materials and methods - Three commercially available provisional materials were chosen - DPI heat cure, Protemp™4 chemical cure and the relatively newer Luxatemp Solar dual cure material. Flat circular metallic dies were prepared of 22 mm diameter and 2 mm thickness. Total 150 samples were prepared from the materials using these dies. The samples were finished and polished using standardized methods. They were divided into five groups. Two groups from each material were subjected to a standardized thermocycling regimen. The samples were immersed in two staining solutions - coffee solution and sambhar curry solution for 30 days. Artificial saliva was used for the control group. The solutions were prepared using a standardized method and were changed every day. The color measurements were done twice - once before thermocycling and staining and once after, in CIE L*a*b* color system using a reflectance spectrophotometer. Results – Statistical analysis was done in SPSS version 20.0 using One-way ANOVA and Tukey’s post-hoc test. p value <0.05 was considered statistically significant. Conclusions – New material Luxatemp Solar showed least color stability, followed by Protemp™4 whereas DPI showed maximum color stability. Sambhar curry showed higher staining ability. The color changes seen with coffee and control were not clinically perceptible. Thermocycled samples showed more color change than non thermocycled samples.