A dose-dependent effect has been demonstrated in the analysis of enamel resistance to a cariogenic challenge following the application of an acidulated phosphate fluoride (APF) or sodium fluoride (NaF) gel, with greater fluoride absorption and a more efficient reduction in demineralisation in enamel treated with APF than with NaF [Delbem and Cury, 2002].
The findings of the present study are in disagreement with those described by Delbem and Cury , who found that APF was more effective at reducing enamel demineralisation under a cariogenic challenge than the NaF gel.
These variables could have affected the inhibition of demineralisation in the present study, as exfoliated primary teeth were used and the application of the fluoride compounds was performed prior to the cariogenic challenge.
The aims of this study were firstly to investigate the resistance to degradation of RMGIC and adhesive/CR restorations in sound and caries-affected primary dentine, submitted to load cycling and cariogenic challenge in vitro, by evaluating nanoleakage.
The pH cycling, however, aimed to simulate the cariogenic challenge that the restorations are subjected to in an environment characterized by caries activity.
The use of restorative material with chemical mechanism of bonding is encouraged in patients with caries activity, because these materials are resistant to cariogenic challenge.