Insights into and relative effect of chitosan-krill oil, chitosan-H-aspirin, chitosan-H-krill oil-nystatin and chitosan-H-krill oil-aspirin-nystatin on dentin bond strength and functional drug delivery capacity: In-vitro studies

Abstract Background: Restorative materials in the new era aim to be “bio-active” and long-lasting. The purpose of this study was to design and to evaluate a novel chitosan hydrogels containing krill oil (antioxidant containing material), nystatin (antifungal), aspirin (pain relieve medication and free radical scavengers) and combinations thereof (chitosan-H-krill oil, chitosan-H-krill oil-nystatin and chitosan-H-aspirin, chitosan-H-aspirin-nystatin, chitosan-H-krill oil-aspirin and chitosan-H-krill oil-aspirin-nystatin) as functional additive prototypes for further development of “dual function restorative materials,” and secondly to determine their effect on the dentin bond strength of a composite. Materials and Methods: The above-mentioned hydrogels were prepared by dispersion the corresponding component in glycerol and acetic acid with the addition of chitosan gelling agent. The surface morphology (scanning electron microscope (SEM)), release behaviors (physiological pH and also in acidic conditions), stability of the therapeutic agent-antioxidant-chitosan and the effect of the hydrogels on the shear bond strength of dentin were also evaluated. Results: The release of nystatin and aspirin confer the added benefit of synergistic action of a functional therapeutic delivery when comparing the newly designed chitosan-based hydrogel restorative materials to the commercially available products alone. Neither the release of nystatin and aspirin nor the antioxidant stability was affected by storage over a 6 month period. The hydrogel formulations have a uniform distribution of drug content, homogenous texture and yellow color (SEM study). All chitosan dentin treated hydrogels gave significantly ( P