Comparison of colour changes of acrylic and composite removable prosthetic teeth in two different bevereges

Abstract

Introduction: The most important feature of any prosthetics is having the most similarity in terms of function, appearance and aesthetics to the lost organ.Staining of artificial teeth has always been one of the major concerns of patients who use dentures. This study was designed to determine the best tooth brand in terms of colour stability and to compare colour change of composite and acrylic teeth. Methods and material: This in vitro experimental study evaluated the colour change of two brands of composite denture teeth (Finex (Iran, Betadent) and Yamahachi(Japan)) and two brands of acrylic denture teeth (Acryplus ( Italy, Ruthinium)and Polident (Slovenia)) after immersion in tea and cola. Distilled water was used as control group. 8 samples from each brand were immersed in tea and cola for a one week and a three-weekperiod. Colour parameters were assessed using a spectrophotometer before and after immersion.Colour change was measured using colour parameters L, a,b . In order to assess the effect of type of drinking solutions and tooth type in colour change in the allotted time, analysis of variance for repeated measurement was applied. For Non-normal data Fridman non parametric statistical test was used.For data analysis SPSS 16 software was used also the level of statistical significance was set to less than 0.05. Results: Analysis of variance for repeated measurements revealed significant differences in the mean colour changes at 7- and 21-day intervals (p-value<0.001).Furthermore, there was a significant difference in the mean colour change of all the teeth in this study (p-value=0.001). Difference in the mean colour change of Finex composite teeth and Polident acrylic teeth was significant (p=0.043). The colour change of Finex was 0.67 less than Polident. Also there was a significant difference between the colour change of Yamahachi composite teeth andPolident(p<0.001). The colour change of Polident was 1.024 more than Yamahachi. The mean colour change between tea and distilled water was significant (p<0.001). Colour change in distilled water was 2.20 less than tea. Also, there was a significant difference between the colour change in distilled water and Cola (p<0.001) the mean colour change in Cola was 1.27 more than distilled water. Furthermore, the mean colour difference between tea and Cola was significant. The amount of colour change in cola was 0.92 less than tea. Conclusions: Within the limitation of this study the following conclusions were drawn: 1. Staining of all denture teeth increased with immersion period 2. Acrylic denture teeth were more susceptible to colour change than composite teeth 3. The most chromogenic staining solution was found to be the tea solution in three weeks immersion period the amount of discolouration caused by this solution was found to be clinically unacceptable. 4. Among the various denture teeth brands Polident denture teeth had the most colour change and Yamahachi composite teeth were found to be the least susceptible to colour change.