Dual-functions of prime-and-rinse approach with MDP primer on the performance of modified self-etch adhesive

Objectives This study introduced the prime-and-rinse approach with an methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primer to augment the performance of modified self-etch adhesives loaded with amorphous fluorinated calcium phosphate (AFCP) nanoparticles. Methods The modified self-etch adhesive was acquired by adding 20 wt% AFCP nanoparticles into Clearfil S3 Bond. An experimental primer containing 15 wt% MDP was prepared. The bond performance was assessed through micro-tensile bond strength (MTBS) tests. Additionally, a single-layer collagen model and demineralized dentin were used to investigate mineralization characteristics. Cytotoxicity was evaluated using a modified transwell insert model on human dental pulp stem cells. Results The incorporation of AFCP nanoparticles into the Clearfil S3 Bond led to a significant reduction in MTBS. While the application of MDP primer could improve the bond performance of modified Clearfil S3 Bond. The MDP primer further augmented the mineralization of single-layer collagen model and demineralized dentin induced by modified self-etched adhesive. The relative cell viability was around 100 % in all groups in the study. Clinical significance These results indicated that the prime-and-rinse approach with MDP primer not only compensated for the reduced bond strength caused by the incorporation of AFCP nanoparticles but also enhanced mineralization capabilities and maintained biocompatibility, offering a promising strategy for improving the longevity of dental restorations.