నైరూప్య

Mirror-polished surface of ceria-stabilized zirconia/alumina nanocomposite enhancement in the adhesion strength of human gingival fibroblasts.

Takahito Osawa, Eri Urano-Morisawa, Fuminori Iwasa, Kazuyoshi Baba

Connective tissue sealing between the transmucosal area of the dental implant surface and the soft tissue is important for the long-term stability of dental implants. This study aimed to investigate the mechanical adhesion strength of the Connective Tissue Equivalents (CTEs) to the Ceria-stabilized Tetragonal Zirconia Polycrystal/Alumina (Ce-TZP/Al₂O₃) surface. We prepared Titanium (Ti) and Ce-TZP/Al₂O₃ disks with different surface roughness, namely, mirrored and machined surfaces, on which HGF-1 were cultured, and then the biological parameters of the cultured cells, including cell morphology and gene expression of focal adhesion proteins were assessed. Furthermore, the mechanical adhesion strength of CTEs to the disk surface was measured using the nano-scratch test. Scanning electron microscopy and atomic force microscopy observation showed smoother morphology on the mirror-polished surface when compared to the mechanically polished surface. A lager expansion of the cell area accompanied by a greater development of actin cytoskeleton and talin1, a greater adhesion strength of CTEs to each disk, and higher gene expression level of focal adhesion protein were observed with the mirror-polished surface than the mechanically polished surface both Ti and Ce-TZP/Al₂O₃ disks. No such differences were found between Ti and Ce-TZP/Al₂O₃ disks. This study provides the first evidence for the mechanical adhesion strength of CTEs to Ce-TZP/Al₂O₃ and Ti surfaces. Mirror-polished Ce-TZP/Al₂O₃ might contribute to the success of implant therapy by its strong adhesion strength to gingival connective tissues with the developed focal contact-cytoskeleton complex.