A 12-months randomized clinical trial comparing fluoride-based remineralising protocols on post-orthodontic initial caries lesions

OBJECTIVES: To compare the long-term remineralization of initial caries lesion (ICL) treated with different remineralizing agents during orthodontic retention using optical coherence tomography (OCT).

MATERIALS AND METHODS: This randomised clinical trial recruited 30 patients on fixed appliances with at least one ICL labially on any maxillary incisor. At debond (baseline), they were allocated to three groups, where twice daily fluoride toothpaste was given: (1) as control; (2) supplemented with daily casein phosphopeptide amorphous calcium phosphate with fluoride (CPP-ACPF); or (3) supplemented with three-monthly professional applied fluoride varnish (FV). Primary outcome was the OCT backscatter reflectance changes of the ICL, measured as integrated reflectivity (IR). Follow-ups were at three-month intervals up to 12 months. The trial was registered with Clinicaltrials.gov (NCT04788550).

RESULTS: Analyses included 26 participants (nine control; nine CPP-ACPF; eight FV). There were significant reduction in integrated reflectivity over time. Post hoc comparisons showed reductions were significant up to 150-micron depth at 6-months, and up to 250-micron depth at both 9- and 12-months follow-up compared to baseline. At 12-months, FV had the lowest IR values, followed by CPP-ACPF and control, but the differences between groups were not significant.

CONCLUSIONS: After 12-months observation, use of fluoridated toothpaste alone or supplemented with either fluoride varnish or CPP-ACPF promotes enamel remineralization up to 250-micron depth.

CLINICAL RELEVANCE: Daily fluoridated toothpaste with regular 3-monthly recall visits from the start of orthodontic retention is recommended for effective control of initial caries lesions. FV and CPP-ACPF supplementation can be considered but their long-term benefits remain inconclusive.