Evaluation effect of chlorhexidine and green tea mouthwash on saliva pH and plaque index

Aims: Applying mouthwash has an important role in reducing caries when compared to other prevention methods. The purpose of this study is to compare saliva pH and plaque index before and after using chlorhexidine mouthwash and a mouthwash with green tea extract. Materials and Methods: Forty dental students were randomly assigned to two groups (chlorhexidine and green tea mouthwash). A week before research getting started and during that, the students were asked to use normal diet and Bass brushing method. Salivary pH and plaque index of the participants were measured before, 1 week, and also 2 weeks after the use of mouth washes. Then, the data were analyzed based on Friedman, Mann–Whitney, and repeated‑measures ANOVA tests. Results: The mean pH was significantly different in the three times of 1 week prior, during, and 2 week after the treatment for the green tea group (P = 0.01). However, there was no significant difference in the chlorhexidine group (P = 0.211). The mean of new plaque in both chlorhexidine green tea groups was significant (P 0.001). The mean of plaque formation at 48 h in chlorhexidine and in green tea was both significant (P 0.001). Conclusion: The effect of chlorhexidine mouthwash and green tea on salivary pH and plaque index was the same in a week. However, the effect of green tea was more than that of chlorhexidine in a 3‑week application.