METHODS: This study included 3 groups with 15 orthodontic patients in each. The control group included patients who had no probiotic treatment, the subjects in the kefir group consumed 2 × 100 ml of kefir (Atatürk Orman Ciftligi, Ankara, Turkey) per day, and the subjects in the toothpaste group brushed their teeth with toothpaste with probiotic content (GD toothpaste; Dental Asia Manufacturing, Shah Alam, Selangor, Malaysia) twice a day. Samples were collected at 3 times: beginning of the study, 3 weeks later, and 6 weeks later. The salivary flow rate, buffer capacity, and Streptococcus mutans and Lactobacillus levels in the saliva were evaluated. Chair-side kits were used to determine the S mutans and Lactobacillus levels.

RESULTS: A statistically significant decrease was observed in the salivary S mutans and Lactobacillus levels in the kefir and toothpaste groups compared with the control group (P <0.05). A statistically significant increase was observed in the toothpaste group compared with the control and kefir groups in buffer capacity. Changes in the salivary flow rate were not statistically significant.