Method: Adolescent patients assigned to receive comprehensive orthodontic treatment (n=54) were randomly assigned to the 3 treatment groups. At initial bonding, group 1 received a mouth rinse containing fluoride, xylitol and a pH neutralizing agent (CariFree®, Oral Biotech, Albany, OR), group 2 received an over-the-counter fluoride mouth rinse (ACT®, Chattem Inc., Chattanooga, TN), and group 3 was not provided with a mouth rinse. All groups received oral hygiene instructions, while groups 1 and 2 also received a supply of mouth rinse and instructions for use per manufacturers’ recommendations. At the start of appointments, plaque specimens were collected from enamel surfaces of maxillary canine teeth adjacent to the orthodontic brackets. The specimens were assayed for total oral bacteria using ATP-driven bioluminescence. Collections were made at the beginning of treatment (T0), and after 6 (T1) and 15 (T2) weeks of treatment. Analyses of intra- and inter-group bacteria counts were made using 2-way ANOVA with Tukey post-hoc comparisons.
Result: Comparing bacteria counts within groups, group 1 showed no significant changes T0 to T1 and T1 to T2. Groups 2 and 3 showed significant increases between T0 and T1 (p<0.05), and no change T1 to T2. Comparison among groups showed no significant differences at T0, T1 or T2.
Conclusion: Intragroup results from the mouth rinse group where fluoride, xylitol and a pH neutralizing agent were used compared to the fluoride or no rinse groups suggest that xylitol and a pH neutralizing agent may be determinative factors preventing significant increases in oral bacterial counts. However, intergroup comparisons indicate caution is needed in drawing such a conclusion.