Spectrophotometric Evaluation of Color Stability of CAD/CAM Monolithic Zirconia Following Exposure to Betel Leaf, Slaked Lime, Areca Catechu, and Tobacco

Abstract

Background and Aim: Discoloration is a major concern with use of tooth colored restotations. Type of restorative marerial and surface treatment are belived to play a major role in this regards. This study sought to compare the color stability of glazed and polished monolithic zirconia ceramic after exposure to betel leaves with slaked lime, areca catechu and tobacco solutions.

Materials and Method: A total number of 64 discs with 10 mm diameter and 2 mm thickness were fabricated from commercially available CAD/CAM zirconia blanks [Aidite (Qinhuangolao) Technology Co. Ltd.] and divided into two groups of 32. Glazing was done in group 1 samples and group 2 was polished using a polishing kit. The CIE L*a*b* color parameter of the samples were measured using a spectrophotometer. The specimens in each of the two groups Group 1 and Group 2 was further divided into 4 sub-groups i.e. 1A, 1B, 1C, 1D for Group 1 and 2A, 2B, 2C, 2D for Group 2 based on immersing in staining solutions used for immersion. After 28 days of immersion period, spectrophotometer recordings were taken. Colour change (ΔE) values were determined by using the Commision Internationale de l’Eclairage L*a*b* (CIELab) colorimetric system. The colour difference (∆E) values was evaluated by calculating the difference in colour by using spectrophotometer. Results were statistically analysed using ANOVA One way test, Tuckey’s Post Hoc test, One Sample t test and Independent sample t test.

Results: Color measurements revealed that immersion of both group 1 and group 2 in tobacco solution and mixture of betel leaves, areca catechu, slaked lime and tobacco solution resulted in significantly higher color change values(p<0.05). These changes were not significantly different between the 2 groups (p>0.05) when immersed in different staining solutions.

Conclusion: No significant difference in staining observed for both polished and glazed groups. The maximum staining potential was shown by combined mixture of betel leaves with slaked lime, areca catechu and tobacco solution followed by tobacco solution and least by betel leaves with slaked lime and areca catechu solution.