Antibacterial Efficacy of 0.5% Aqueous Piper betle Leaf Extract and 0.2% Chlorhexidine as Mouth Rinse in High Caries Risk Population – An In vitro and an In vivo Real-time Polymerase Chain Reaction Study

A BSTRACT Context: Current caries management strategies prioritize prevention approaches focusing on microbial control using natural antimicrobial products, which are gaining attention for safety and fewer side effects compared to synthetic alternatives. Aim: In vitro antibacterial efficacy of 0.5% aqueous BL extract and 0.2% chlorhexidine (CHX) and assesses their influence on pH of saliva and plaque, buffering capacity (BC), and bacterial levels in high-caries risk (HCR) patients. Methodology: BL extract was prepared using the cold maceration method and characterized by the high-performance liquid chromatography. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined against Streptococcus mutans and Lactobacillus acidophilus . In vivo analysis involved 24 patients divided into three groups: 0.5% aqueous BL extract (Group I), 0.2% CHX (Group II), and placebo (Group III). Prerinse and postrinse samples were collected from saliva, plaque, and caries sites at 60 min and 24 h. Salivary BC, salivary and plaque pH, and bacterial quantification were assessed using Ericsson’s method, pH meter and real-time polymerase chain reaction (PCR), respectively. Statistical Analysis: Kolmogorov–Smirnov test, Shapiro–Wilk test, and nonparametric Kruskal–Wallis test. Results: MIC and MBC of CHX are 250 μg/mL and 1000 μg/mL, whereas BL extract was 500 μg/mL and 5000 μg/mL, respectively. Groups I and II showed an increase in salivary pH and BC, as well as plaque pH ( P > 0.05) after mouthrinse use. Real-time PCR resulted a reduction in bacterial DNA copies for both groups postrinse ( P > 0.05). Conclusions: 0.5% aqueous BL extract demonstrated antimicrobial activity comparable to 0.2% CHX mouthrinse. BL mouthrinse could be a potential natural alternative to CHX in HCR patients.