Chewing Gum: Effect on pH and Streptococcus Mutans of Saliva

Objectives: The purpose of this study was to evaluate the effects of four commercial chewing gums on streptococcus mutans and pH of saliva. Methods: This study was conducted over seven weeks in association with four groups including thirty day-night high school female students. One group consisted commercial sucrose-containing gum named Aidin (group A), three groups for commercial sugar-free gums named Relax (group B ), Dirol (group C )and Happydent (group D). All of the gums were obtained from one of the gum distributing centers in Iran. The participants used three gum sticks daily after main meals, for about five minutes. The sampling of saliva was performed unstimulated after waking up and before brushing the teeth, three times: at baseline, after three weeks and after seven weeks. Results: In the first three weeks of the study, all groups even sucrose-containing gum group showed a significant decrease on the salivary streptococcus mutans, and there were no differences between groups. But between weeks three to seven the decreases were only significant in groups C and D. However, despite week three, at week seven there was a significant difference between groups A and B, C, D on decreasing of salivary streptococcus mutans. Salivary pH significantly decreased only in group A during the seven weeks of study and the difference was significantly observed between groups A and D. There were also significant increase on the salivary bacterial colonies (other than streptococcus mutans) in group B during the seven weeks of study. Conclusions: Despite the results of some previous studies, this study showed that three weeks chewing any gums even sucrose-containing gum after main meals can decrease the level of salivary streptococcus mutans. However, during the seven weeks, the decreasing effects of consuming sugar-free gums were significantly higher.