RESUMO
STATEMENT OF PROBLEM: Polyvinylphosphonic acid (PVPA) could be used as a biomimetic remineralization analog and a matrix metalloproteinases (MMPs) inhibitor. However, studies are lacking regarding the performance of PVPA in dental bonding systems for maintaining the durability of the resin-dentin bond. PURPOSE: The purpose of this in vitro study was to investigate the effect of PVPA on the durability of resin-dentin bonds and the viability of mouse dental papilla cell-23 (MDPC-23). The mechanical properties of resin-dentin interfaces during long-term storage were analyzed, and the potential application of PVPA as a biomimetic remineralization analog in adhesive dentistry was evaluated. MATERIAL AND METHODS: Seventy-five extracted noncarious human third molars were collected and randomly divided into 5 groups, and then the microtensile bond strength (µTBS) data and scanning electron microscope (SEM) images were used to evaluate the preservation condition of resin-dentin bonds after 1 day, 6 months, and 1 year of storage. The cytotoxicity of PVPA was detected by cell proliferation assay and cell apoptosis assay. RESULTS: Compared with the control and chlorhexidine (CHX) groups, the combined group (treated with both 200-µg/mL PVPA and biomimetic remineralization) had excellent bond durability. The exposed collagen fibril from the PVPA-treated groups (included 200-µg/mL and 500-µg/mL PVPA groups and a combined group) still showed integrity after 1 year of storage when compared with the control group. PVPA up to 500 µg/mL showed no cytotoxicity to MDPC-23 and did not inhibit cell growth. CONCLUSIONS: This study offered evidence that PVPA did not result in cytotoxicity at low concentrations as an MMP inhibitor and a biomimetic remineralization analog. In addition, the application of PVPA improved bond strength and preserved collagen integrity after 1 year of in vitro storage.
