Effects of Different Remineralisation Agents and Adhesives Around Orthodontic Brackets: Is There a Relationship Between Remineralisation and Shear Bond Strength?

Purpose: The aim of this in-vitro study was to evaluate the effects of different remineralisation agents and adhesives on the remineralisation of white spot lesions (WSL) using quantitative light-induced fluorescence (QLF) and the shear bond strength (SBS) of brackets. Materials and Methods: One hundred fifty premolars were bonded with Transbond XT and resin-modified glass-ionomer cement (RMGIC). WSL were created using a demineralization solution and an APF gel, Tooth Mousse (TM) and Duraphat were applied for remineralisation. WSL were evaluated using QLF and SBS of brackets and tested using an Instron testing machine. Paired-samples t-test, independent-samples t-test and one-way ANOVA were used for comparisons of the ∆F, area and SBS. Post-hoc tests were performed using Tukey's test. Results: In the Transbond group, all remineralisation agents provided remineralisation, with Duraphat producing greater improvement. In terms of lesion area, the positive control and APF gel group values were close to each other, and a statistically significant improvement was observed in the TM and Duraphat groups' areas. In the RMGIC group, with TM application, the ΔF value was statistically significantly higher; area differences between the APF and TM groups were not statistically significant. The Transbond group showed greater SBS than did RMGIC, and in the Transbond group, Duraphat had the highest SBS value. Conclusions: In bonding with Transbond, the Duraphat group demonstrated greater improvement than other remineralisation agents. In the RMGIC group, the best remineralisation was obtained by TM. The Transbond XT and Duraphat combination provided the highest SBS values. Keywords: casein phosphopeptide-amorphous calcium phosphate, fluoride gel, fluoride varnish, remineralisation, shear bond strength, quantitative light-induced fluorescence, white spot lesions