Spectrophotometric analysis of the color stability of white mineral trioxide aggregate in contact with four different irrigating solutions - An in vitro study

AIMS: This study aims to compare the color stability of white mineral trioxide aggregate (wMTA) in contact with four irrigating solutions. SETTINGS AND DESIGN: Original research study. SUBJECTS AND METHODS: Fifty cylindrical discs of wMTA, 10 mm in diameter and 2 mm in height were prepared using a mold. Samples were incubated at a temperature of 37°C and at 100% humidity for the material to reach its optimal mechanical properties. The samples were divided into 6 groups: Group A: dry (n = 5); Group B: distilled water (DW) (n = 5); Group C: 5% sodium hypochlorite (NaOCl) (n = 10); Group D: 2% chlorhexidine gluconate (CHX) (n = 10); Group E: 17% aqueous ethylene diamine tetra-acetic acid (EDTA) (n = 10); Group F: 0.2% Chitosan (n = 10) Each disc was immersed into the irrigating solution for a period of 24 h. All the specimens were photographed using a digital camera before and after immersion. The assessment of color change of each disc of wMTA was conducted by a spectrophotometer. The Commission Internationale de l'eclairage system was used to calculate the differences in color. STATISTICAL ANALYSIS USED: Statistical Package for the Social Sciences version 16.0 (Chicago, IL, USA) at a significance level of P < 0.05 was used. RESULTS: All groups except group A exhibited discoloration of wMTA. The mean values for change in color was highest with Group D, followed by Group C, F, E, B, and group A. Only Group B when compared to group A did not show any statistically significant difference (P = 0.948) whereas all the other four groups showed a highly statistically significant difference (P < 0.001). CONCLUSIONS: 2% CHX causes maximum discoloration of wMTA followed by 5% NaOCl, 0.2% Chitosan and least discoloration with 17% aqueous EDTA and DW.