Effect of the probiotic bacterium Lactobacillus reuteri on white spot lesion development in orthodontic patients.

Background/objectives: The purpose of the study is to evaluate the effect of daily intake of lozenges containing probiotic bacteria on white spot lesion (WSL) formation as well as on salivary lactobacilli (LB) and mutans streptococci (MS) counts, in patients undergoing orthodontic treatment with fixed appliances.

Materials/methods: A randomized double-blind placebo-controlled study design with two parallel arms was employed. Patients (n = 85, mean age 15.