Efficacy of chitosan-based chewing gum on reducing salivary S. mutans counts and salivary pH: a randomised clinical trial

Objective: To determine chitosan-based chewing gum role on reducing salivary S. mutans counts and salivary pH.

Materials and methods: The present double-blind randomised clinical trial with the trial registration number of IRCT20190724044319N1 was conducted on 36 dental students. The volunteers were, randomly, divided into two groups (n = 18) including: G1: intervention group (chitosan chewing gum) and G2: control group (placebo chewing gum). Each participant was given eight pieces of the chewing gum, and was asked to chew each gum piece for 5 min and this was repeated for eight times. Their Saliva was collected before and after chewing gums and the number of S. mutans colonies and salivary pH were determined. Data were analysed using SPSS (ver.21) and independent student t test. p Value less than .05 was set as significant.

Results: There was significant difference between two groups for the number of salivary S. mutans colonies ($3{.31*10}^5$ in the intervention group compared to ${13.94*10}^5$ in the Control group) (p < .001). The salivary pH evaluation showed that salivary pH mean value in intervention group was not significant in compared with control group (p = .17). However, the chitosan chewing gum led to an increase in salivary pH by 0.17, which was statistically significant (p = .01).

Conclusion: Results of this study showed that chitosan chewing gum has a positive effect on the reduction of numbers of salivary S. mutans colonies but had no considerable effect on the increase of salivary pH.