Impact of a non‐fluoridated microcrystalline hydroxyapatite dentifrice on enamel caries progression in highly caries‐susceptible orthodontic patients: A randomized, controlled 6‐month trial

Aim The aim of the present randomized, controlled trial was to compare the impact of the regular use of a fluoride‐free microcrystalline hydroxyapatite ( HAP ) dentifrice and a 1400 ppm fluoride control dentifrice on caries progression in 150 highly caries‐active orthodontic patients. Methods The primary outcome was the occurrence of lesions with International Caries Detection and Assessment System ( ICDAS ) ≥code 1 on the vestibular surfaces of teeth 15‐25 within 168 days after fixation of orthodontic brackets. Secondary outcomes were lesion development ICDAS ≥code 2, the plaque index, and the gingival index. Results In total, 147 patients were included in the intent‐to‐treat ( ITT ) analysis; 133 finished the study per protocol ( PP ). An increase in enamel caries ICDAS ≥code 1 was observed in 56.8% ( ITT ) and 54.7% ( PP ) of the HAP group participants compared with 60.9% ( ITT ) and 61.6% ( PP ) of the fluoride control group. Non‐inferiority testing ( ITT and PP ) demonstrated the absence of a significant difference between the groups. No significant differences in secondary outcomes were observed between the groups. Conclusion In highly caries‐active patients, the impact of the regular use of a microcrystalline HAP dentifrice on caries progression is not significantly different from the use of a 1400 ppm fluoride toothpaste (ClinicalTrials.gov: NCT 02705456).