Evaluation of surface roughness and Vickers microhardness of various nano-herbal extracts on demineralized dentin and their bactericidal efficacy with 970-nm wavelength diode laser irradiation

Abstract

Abstract Objective Was to evaluate effect of clove, turmeric and garlic nano-herbal extracts on surface roughness and microhardness of demineralized dentin, and their bactericidal effect on Streptococcus mutans and Streptococcus sobrinus with or without diode laser irradiation. Methods Three 5% nano-formulas were prepared and characterized using transmission electron microscope. MI paste Plus™ was used as control. A total of 100 specimens of demineralized dentin were prepared and treated with 3 W-power diode laser; then, the different tested materials for 10-min before the surface roughness and Vickers microhardness tests were conducted. Eighty coronal cavities were prepared (1-mm diameter × 2-mm depth). Cavities were inoculated with the tested materials with S. mutans or S. sobrinus bacteria, with or without diode laser irradiation for 20-s. Colony-forming unit method was used for counting the viable bacteria. Data were explored for normality using Kolmogorov–Smirnov and Shapiro–Wilk tests and showed parametric distribution for the surface roughness and microhardness tests, and non-parametric distribution for the bactericidal activity test. Results The herbal formulas had a significant surface roughness and microhardness mean values. It showed a significant antimicrobial effect on the tested bacteria. When they were combined with diode laser, they showed a significantly higher antimicrobial effect. Conclusions The tested herbal formulas represent potent topical remineralizing and antibacterial agents especially when they are used in conjunction with diode laser irradiation.

Keywords

• Surface roughness
• Vickers microhardness
• Antibacterial effect
• Nano-herbal extracts
• Streptococcus mutans
• Streptococcus sobrinus