Evaluation of The Effect of Three Different Mouthwashes on The Surface Microhardness And Colour Stability of A Bioactive Restorative Material – An in Vitro Study

Abstract

Context: The performance of bioactive restoratives clinically is highly dependent on their ability to withstand exposure to chemical agents in the oral cavity. 

Aims: To evaluate the effect of three different mouthwashes on the surface microhardness and colour stability of the bioactive restorative material ACTIVA™ BioACTIVE.

Materials and Methods: Seventy-two disc-shaped samples of ACTIVA™ BioACTIVE (8 mm diameter, 1 mm thickness) were fabricated and randomly assigned to four groups of 18 samples each. Group 1 (artificial saliva – control), Group 2 (Listerine^® Cool Mint^®), Group 3 (Sensodyne Complete Protection+), and Group 4 (Himalaya Active Fresh Miswak). Following a continuous 24-hour immersion at 37°C, surface microhardness was measured using a Digital Vickers hardness tester. Colour stability (∆E) was assessed via spectrophotometry using the CIE L*a*b* system.

Statistical Analysis: Data were analysed using descriptive statistics, one-way ANOVA, and Tukey HSD post hoc tests with the significance threshold set at p ≤ 0.05.

Results: Significant differences were observed across all experimental groups (p < 0.001). Group 1 showed the highest stability. Among the mouthwashes, Listerine caused the greatest reduction in microhardness and the highest colour change. Sensodyne and Himalaya exhibited significantly better microhardness retention, while Sensodyne demonstrated superior colour stability.

Conclusion: Alcohol-containing Listerine mouthwash significantly compromised the surface microhardness and colour stability of ACTIVA™ BioACTIVE. Non-alcoholic Sensodyne and herbal Himalaya mouthwashes were more compatible, maintaining material properties within acceptable clinical limits.