Comparison of color stability of different coated esthetic orthodontic archwires using spectrocolorimeter – An invitro study

Aim: The aim of this study was to evaluate and compare the colour stability of three different esthetic archwires (rhodium, teflon and epoxy coated) immersed in three different staining solutions (tea, coffee and artificial aerated orange drink) at different time intervals (0, 7, 14, 21, 45 day) using spectrocolorimeter and also to determine the most chromogenic agent. Materials and Methods: A total of 54 esthetic coated archwires (rhodium, teflon and epoxy) were evaluated. They were divided into 3 groups (archwires) with each group having 3 subgroups (staining solutions) and six samples in each sub group. The baseline value (T0) was measured before the samples were immersed in the staining solutions. The samples were immersed in the staining solution for 3 hours a day for 45 days. The ?E values were recorded on 7, 14, 21 and 45 day using spectrocolorimeter. Using these values NBS units were calculated. The experimental data were analyzed using descriptive statistics, analysis of variance, and post hoc Bonferroni test. Results: It was found that teflon coated esthetic archwires were the least colour stable when compared with rhodium and epoxy coated esthetic archwires. Artificial aerated orange drink caused higher ?E* values than tea and coffee. The ?E* value increases as the time interval increases. Conclusions: All esthetic archwires evaluated in the present study were stained the most by an artificial aerated orange drink in comparison with coffee and tea. The overall study outcome indicates that archwires coated with epoxy resin are more advisable for patients because of their colour stability. Keywords : Colour stability, Esthetic archwires, Staining solutions, Spectrocolorimeter.