Comparative Analysis of Antimicrobial Properties and Physical Properties of Mineral Trioxide Aggregate Mixed With Distilled Water, Chlorhexidine, and Sodium Hypochlorite Solutions: An In Vitro Study

Abstract

BACKGROUND:  Endodontics widely uses mineral trioxide aggregate (MTA) because of its excellent sealing ability, biocompatibility, and capacity to promote healing. However, the effectiveness of MTA can vary depending on the blending solution used. Endodontics commonly employ chlorhexidine (CHX) and sodium hypochlorite (NaOCl), but their impact on MTA's properties necessitates further investigation. MATERIALS AND METHODS: We blended MTA with the specified solutions and prepared it for testing according to the manufacturer's instructions. The study was divided into four groups: group 1 involved MTA blended with distilled water, group 2 consisted of MTA blended with 0.12% CHX solution (PerioGard, Colgate-Palmolive, Osasco, Brazil), group 3 included MTA blended with 0.2% CHX solution (Corsodyl, GlaxoSmithKline Consumer Healthcare, England, UK), and group 4 comprised MTA blended with 5% NaOCl (Azure Research Lab Pvt. Ltd., New Delhi, India). The antimicrobial activity of each group was assessed using the agar diffusion method against Enterococcus faecalis, Candida albicans, and Streptococcus mutans. We measured the compressive strength at 1, 3, 7, and 21 days using an Instron universal testing machine (Hounsfield Test Equipment, Redhill, UK). Statistical significance was evaluated through one-way ANOVA and Kruskal-Wallis tests, with p values <0.05 considered significant. RESULTS:  Group 3 (MTA blended with 0.2% CHX) exhibited the highest antimicrobial efficacy, with significantly larger inhibition zones against Enterococcus faecalis (25.25 ± 0.21 mm vs. 13.33 ± 0.12 mm, p = 0.011), Candida albicans (29.58 ± 0.24 mm vs. 16.97 ± 0.16 mm, p = 0.004), and S. mutans (26.37 ± 0.15 mm vs. 14.55 ± 0.25 mm, p = 0.027). Group 4 (MTA blended with 5% NaOCl) showed the highest compressive strength at one and three days (p = 0.032 and p = 0.021, respectively), but by 21 days, group 2 demonstrated the greatest compressive strength (p = 0.044). CONCLUSION:  MTA mixed with 0.2% CHX provides superior antimicrobial properties, making it suitable for enhanced microbial control in endodontic treatments. Conversely, MTA mixed with 0.12% CHX offers optimal long-term compressive strength. These findings guide selecting MTA formulations to maximize performance based on clinical needs.