Evaluation of Salivary pH and Viability of Streptococcus Mutans after Chewing Neem and Mint Leaves: An in vivo Study

Abstract

Neem and mint leaves are well recognized in traditional Indian medicine for their stimulant, antiseptic, antifungal, and antibacterial properties. They have been incorporated into toothpastes and mouthwashes as natural anti-caries agents. Streptococcus mutans has a significant role in the development and worsening of dental caries. The present study aimed to assess the changes in salivary pH and the viability of Streptococcus mutans following the chewing of neem and mint leaves. A total of 60 saliva samples were collected from 30 subjects, both before and after chewing neem and mint leaves. Salivary pH was measured using pH indicator strips. All the samples are diluted to 1:160 and inoculated on Mutans-Sanguis agar plates, which were then incubated at 37°C for 24 hours. The bacterial colonies were counted, and the data were analysed with the Paired Sample T-Test. The average number of colonies seen prior to eating neem and mint leaves was 41.90, which decreased to 25.80 after chewing. This decrease was statistically significant (p = 0.004; p < 0.05). The average salivary pH rose from 5.995 before chewing to 6.190 after chewing, while the difference was not statistically significant (p = 0.081; p>0.05). Chewing neem and mint leaves resulted in a significant decrease in Streptococcus mutans colony counts, suggesting antibacterial action. While salivary pH increased somewhat, it was not statistically significant.