Polymerization kinetics of hydrophilic-rich phase in phase-separated dentin adhesives

Abstract

calcium phosphate depositions were searched by scanning and transmission electronmicroscopy, elemental analysis and X-ray diffraction. Nanoparticles in ethanol solution were infiltrated in phosphoric acid etched human dentin and single bond (3M/ESPE) was applied as adhesive, in order to perform a microtensile bond strength test, after 24h. Debonded sticks were analyzed by scanning electron microscopy. Numerical data were analyzed by ANOVA and Student–Newman–Keuls multiple comparisons tests (p<0.05). Results: Nanoparticles (NPs) were effectively zinc-loaded and have been shown to have a potent quelant effect, retaining calcium regardless of zinc incorporation. NPs superficially infiltrated demineralized dentin and remained embedded at the hybrid layer, without altering bond strength. Calcium and phosphorus were found covering nanoparticles at the hybrid layer, after 24h. Mean and standard deviation of microtensile bond strength to dentin and mode of failure of experimental groups are presented in the table (A: adhesive; C: cohesive; M: mixed) Conclusion: Tested nanoparticles may be incorporated as fillers into dental adhesives in order to provide the appropriate environment inwhichmineral growthmay occur. Capacity for controlled ion/protein delivery should be further investigated.