The effects of cyclodextrin on plaque accumulation in healthy Japanese adults: A randomized, placebo-controlled, double-blind, parallel-group comparison study

Background: Cyclo-isomalto-oligosaccharides (CI) have been reported to inhibit glucosyltransferases (GTF) in vitro. GTF is an enzyme related to oral plaque synthesis. However, there are few clinical studies to investigate the effect of CI on oral plaque via inhibiting GTF activity. Objective: The purpose of this study was to evaluate the inhibitory effect of consuming CI-Dextran mix on plaque accumulation in healthy Japanese adults. Methods: This randomized, placebo-controlled, double-blind, parallel-group comparison study was conducted from May 26, 2022, to September 16, 2022. Individuals who agreed to participate in the study were randomly assigned to the CI-Dextran mix group with 60 mg/day (n = 22), the CI-Dextran mix group with 600 mg/day (n = 11), or the placebo group (n = 22). The intervention period was three days, and the outcome of this study was the plaque index (PlI), an indicator of plaque accumulation.  Results: Our results showed that the CI-Dextran mix group (600mg/day) had significantly lower post-intervention PlI values than the placebo group in a full analysis set (FAS). In individuals identified as prone to plaque accumulation among the FAS, both CI-Dextran mix groups showed significantly lower PlI values than the placebo group. No adverse events were observed during the study period, and consumption of the test food under the study conditions was considered safe. Conclusions: Our results clearly indicated that a high dose of CI-Dextran mix (600 mg/day) could significantly reduce plaque formation in healthy Japanese adults, while a marginal reduction was noted for the group taking a low dose (60 mg/day). In particular, intake of both doses (CI-Dextran mix 60 mg/day and 600 mg/day) in individuals who were prone to plaque accumulation, could significantly inhibit plaque formation. Keywords: CI-Dextran mix, cyclodextran, plaque inhibition, functional carbohydrates, isomaltooligosaccharide, Randomized Controlled Trial Trial registration: UMIN000047901. Foundation: Nissin Sugar Co., Ltd.