Promoted Abutment-Soft Tissue Integration Around Self-Glazed Zirconia Surfaces with Nanotopography Fabricated by Additive 3D Gel Deposition

Abstract

Introduction Improving the biological sealing around dental abutments could promote the long-term success of implants. Although titanium abutments have a wide range of clinical applications, they incur esthetic risks due to their color, especially in the esthetic zone. Currently, zirconia has been applied as an esthetic alternative material for implant abutments; however, zirconia is purported to be an inert biomaterial. How to improve the biological activities of zirconia has thus become a popular research topic. In this study, we presented a novel self-glazed zirconia (SZ) surface with nanotopography fabricated by additive 3D gel deposition and investigated its soft tissue integration capability compared to that of clinically used titanium and polished conventional zirconia surfaces. Materials and Methods Three groups of disc samples were prepared for in vitro study and the three groups of abutment samples were prepared for in vivo study. The surface topography, roughness, wettability and chemical composition of the samples were examined. Moreover, we analyzed the effect of the three groups of samples on protein adsorption and on the biological behavior of human gingival keratinocytes (HGKs) and human gingival fibroblasts (HGFs). Furthermore, we conducted an in vivo study in which the bilateral mandibular anterior teeth of rabbits were extracted and replaced with implants and corresponding abutments. Results The surface of SZ showed a unique nanotopography with nm range roughness and a greater ability to absorb protein. The promoted expression of adhesion molecules in both HGKs and HGFs was observed on the SZ surface compared to the surfaces of Ti and PCZ, while the cell viability and proliferation of HGKs and the number of HGFs adhesion were not significant among all groups. In vivo results showed that the SZ abutment formed strong biological sealing at the abutment–soft tissue interface and exhibited markedly more hemidesmosomes when observed with a transmission electron microscope. Conclusion These results demonstrated that the novel SZ surface with nanotopography promoted soft tissue integration, suggesting its promising application as a zirconia surface for the dental abutment.

Biological Response of the Peri-Implant Mucosa to Different Definitive Implant Rehabilitation Materials

“…Characteristics such as surface roughness, surface energy, and the relationship of the material with the gingiva influence the state of the peri-implant mucosa and bacterial proliferation [ 37 ]. Many current studies present different systems for modifying the zirconium oxide surface to improve its biological properties [ 38 , 39 , 40 , 41 ]. A smooth surface promotes good soft tissue sealing and less bacterial colonization [ 42 ].…”