Sodium fluoride mouthrinse used twice daily increased incipient caries lesion remineralization in an in situ model

Objectives: To investigate the remineralizing effects of fluoride mouthrinses used at different times and frequency in addition to fluoride toothpaste. Methods: A randomized crossover single blinded study comprised 4 experimental phases of 21 days each. Twelve orthodontic volunteers were fixed with an orthodontic bracket containing an artificial carious enamel slab, which was from the same tooth in all 4 phases, and were randomly assigned to the following groups: (1) brushing with F toothpaste 2x per day (F-brush), (2) F-brush + rinsing with 0.05% NaF (F-rinse) after lunch, (3) F-brush + F-rinse before bedtime, and (4) F-brush + F-rinse 2x per day. Mean mineral gain after each phase was determined from mineral density profiles obtained using Micro-CT. Results: The mean mineral gain in all treatments with F-brush and F-rinse were significantly greater than those in F-brush (p < 0.05). Moreover F-rinse 2x per day increased lesion remineralization more than F-rinse once a day. Conclusions: The twice-daily use of 0.05% NaF mouthrinse combined with twice-daily regular use of fluoride toothpaste resulted in the greatest remineralization of incipient caries. These data indicate that rinsing frequency is a factor affecting the effectiveness of fluoride mouthrinse. Clinical significance: The rinsing frequency of NaF mouthrinse, when used with fluoride toothpaste, also affects the remineralization. This finding, if confirmed by a clinical study, would lead to a new recommendation for fluoride mouthrinse used in high caries risk patients who could benefit from using it twice a day. (C) 2014 Elsevier Ltd. All rights reserved.