The effect of autoclave on dental shade guide

The gradual color change of the tooth shade guide is due to the use of an autoclave is one of the clinical problems for correct color reproduction. The purpose of this research was study the effect of autoclave on dental shade guide. This experimental experiment was experimental and done on 20 dental paints guide (vitaA3). Subsequently, they were divided into 2 groups color guide by randomly. First, all specimens were washed Before placing in the autoclave Distilled for 3 minutes and they were dry with a tissue and they went on to the autoclave, of course The first group is at 121 °C for 40 minutes and the second group was kept at 134 °C for 10 minutes. These specimens were placed in an autoclave with 180 cycles and3 times a day, 5 days a week (equivalent to 3 months). At each stage set the Spectrophotometer color Indicators (abl) and Guide the color of the teeth. Statistical analysis was performed in SPSS software and in the way of Mann-Whitney. Mean in the group with a temperature of 121 degrees was 3.79 ± 0.63 and in the group with a temperature of 134 degrees, it was 3.55 ± 1.04 which are not significant. According to the statistical test, there is a difference (P <0.3). About b and c index, difference were minor and no significant difference was observed in the case of other measured indicators, L, a, H in the two groups.(P<0.2). The color change was more than 3.3 for both method and not acceptable related to clinical subjects. (3.55 and 3.79) In this study, it was observed that sterilization process by autoclave, can lead to change the color properties of the classic VITA color guide.