Measuring Enamel-Remineralisation during the Retention Phase of Orthodontic Treatment

Objectives: To measure longitudinally using Quantitative Light-induced Fluorescence (QLF), the effect of a low fluoride toothpaste (250ppm Na F) on remineralising early White Spot Lesions (WSL) during the retentive phase of orthodontic treatment.

Methods: Patients, who had completed fixed orthodontic treatment, were screened according to inclusion criteria and enrolled for a double blinded randomised controlled trial (RCT) that was assessing the efficacy of different toothpaste regimes to promote remineralisation. 30 patients in a low F group completed the trial.

QLF images of six upper and lower anterior teeth (canine to canine) of patients were recorded and analysed. Each participant was then provided with the toothpaste and toothbrush and asked to brush their teeth twice daily for 2 minutes for 12 months. The participants were asked to refrain from any other oral hygiene products. QLF images were obtained at debond, 2 weeks, 1, 3, 6 and 12 months. Paired T test analysis determined any significant remineralising effects within the group at the various time intervals when compared with the baseline QLF (DQ) values.

Results: A total of 135 WSL were recorded and monitored (WSL most occurring on FDI 22). Earliest remineralisation effect was noticed at 3 months (p=0.039). There was a significant effect observed in the remineralisation of the lesions at 6 and 12 months at 0.01 levels. Significant differences between the 6 month visit and 12 month visit were found (p=0.013). There was a 29.6% reduction in WSL area after 12 months.

Conclusion: Daily application of low fluoride toothpaste was of benefit in remineralising WSL during the retentive phase of orthodontic treatment.