Objectives: White spot lesions (WSLs) are a complication of orthodontic therapy. This study investigated the effect of MI (minimally invasive) Paste Plus (MIPP) and MI Varnish (MIV) on WSLs in orthodontic patients during a 12-month, randomized, single-blind, prospective, standard-of-care controlled clinical trial.
Materials and methods: Forty subjects, recruited from the UCSF School of Dentistry Orthodontics Clinic, were randomly assigned to the experimental (twice-daily 1100 ppm fluoride toothpaste, daily MIPP, quarterly MIV application) or control group (twice-daily 1100 ppm fluoride toothpaste, fluoride rinse recommendation). Facial surfaces of incisors, canines, and first bicuspids were evaluated at baseline, 3, 6, and 12 months using the enamel decalcification index (EDI) and the international caries detection and assessment system (ICDAS).
Results: Findings from 37 subjects are reported. At 12 months, teeth receiving experimental treatment were at lower but not significantly different odds of increased EDI scores (odds ratio, OR 0.63; intra-patient cluster-adjusted 95% CI 0.43, 1.18) and not associated with increased ICDAS scores (OR 0.99; 95% CI 0.64, 1.54). There was no statistically significant difference in mean patient-level EDI sum (experimental group 40.2; control 41.3; t test p = 0.80), ICDAS score (experimental 22.3; control 22.6; Mann-Whitney U test p = 0.80), or percentage of scored surfaces with ICDAS > 0 (experimental 54.6%; control 55.2%; t test p = 0.88). Salivary fluoride levels were significantly higher at 12 months for the experimental than for the control group (0.20 ± 0.26 versus 0.04 ± 0.04 ppm, Mann-Whitney U test p < 0.01).
Conclusions: Applying daily MIPP and quarterly MIV resulted in no statistically significant differences in EDI sum and ICDAS scores. Higher salivary fluoride levels in the experimental group suggest that MIPP and MIV effectively deliver fluoride when used clinically.
Clinical relevance: Daily MIPP and quarterly MIV applications do not appear to reduce significantly WSLs incidence during fixed orthodontic treatment.
Keywords: Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP); MI Paste Plus; MI Varnish; Orthodontic brackets; Randomized controlled single-blind prospective clinical trial; Salivary fluoride level; White spot lesions.