Evaluation of bond durability, surface morphology, and remineralization at the adhesive interface with dentin bonding agents modified with silica-doped nanohydroxyapatite

• Main Authors: Prasanthi Gonapa (Author), Girija S Sajjan (Author), Arun Bhupathi (Author), Uday K Podugu (Author), Suvarna Sundar (Author), Durgabhavani Gondi (Author), R Tejasree Rathod (Author)
• Format: Book
• Published: Wolters Kluwer Medknow Publications, 2022-01-01T00:00:00Z.
• Subjects: article
• Online Access: Connect to this object online.
• Notes: 0976-237X; 0976-2361; 10.4103/ccd.ccd_321_21
• Keywords: dentin bonding agents; microshear bond strength; nanohydroxyapatite; remineralization; silica-doped nanohydroxyapatite; Dentistry; RK1-715
• Source: Contemporary Clinical Dentistry, Vol 13, Iss 4, Pp 356-362 (2022)

Objectives: To compare and evaluate the bond durability, surface morphology, and remineralization of the adhesive layer with newer adhesive systems modified with novel bioactive nanoparticles. Methodology: Bonding agents evaluated in this study include (a) Conventional dentin bonding agent (CN-DBA) (b) Nanohydroxyapatite (nanoHAP) incorporated dentin bonding agent (NH DBA); (c) Silica doped nanohydroxyapatite (Si nanoHAP) incorporated dentin bonding agent (Si NH DBA). A total of 104 human dentin discs (5 mm × 5 mm × 2 mm) were sectioned. Elemental analysis (Ca/P ratio) and surface morphology of the adhesive layer with different dentin adhesives were evaluated under scanning electron microscopy with energy-dispersive X-ray analysis after speculated storage time of 1 day and 6 months. Microshear bond strength of adhesive restorations with different dentin adhesives was evaluated under universal testing machine and fractographic analysis under scanning electron microscope after speculated storage time of 1 day and 6 months. The results were analyzed using analysis of variance and post hoc analysis. Results: Si-NH-DBA showed highest mean microshear bond strength for both 1 day and 6 months, which was significantly higher compared to conventional nanofilled dentin bonding agent (CN-DBA) and NH-DBA. Si-NH-DBA group showed only 10% reduction in bond strength after 6 months, which was less compared to that of other groups. Similarly, Si-NH-DBA showed higher remineralization with stellate-shaped crystals at the adhesive layer after 6 months with hydrolytic resistant hybrid layer, compared to CN-DBA and NH-DBA. Conclusion: Silica-doped nanohydroxyapatite proved its efficiency on bond stability, remineralization, and hydrolytic resistance when incorporated into dentin bonding agents because of its bioactivity and carbonate-containing apatite-forming ability.