The bactericidal and biofilm removal effect of super reducing water on Streptococcus mutans in three types of orthodontic brackets.

Purpose: To investigate the bactericidal and biofilm removal effect of super reducing water (SRW) on Streptococcus mutans (S. mutans) adhered to orthodontic brackets, in vitro.

Methods: Three types of brackets were bonded to aluminum disks. After the formation of S. mutans biofilms on the surfaces, the brackets were divided into three groups (n = 44 each) based on their exposure to SRW: group 1, no treatment; group 2, treated for 5 min; and group 3, treated for 10 min. Total viable counts, adenosine triphosphate measurements, crystal violet assay, and scanning electron microscopy were used to evaluate the effect of SRW.

Results: The bacterial counts in groups 2 and 3 were significantly lower than those in group 1 (P < 0.001); however, no significant differences were observed between groups 2 and 3. Marked decreases in the number of bacterial colonies and extent of biofilm formation were observed in groups 2 and 3 compared to group 1. No significant differences in the number of bacterial colonies and amount of biofilm were observed among the three types of brackets in each group.

Conclusion: These findings indicate the bactericidal and biofilm removal effect of SRW treatment on S. mutans adhered to orthodontic brackets.