Osseointegration of Alkali-Modified NANOZR Implants: An In Vivo Study

Abstract

Ingredients and surface modification methods are being continually developed to improve osseointegration of dental implants and reduce healing times. In this study, we demonstrate in vitro that, by applying concentrated alkali treatment to NANOZR with strong bending strength and fracture toughness, a significant improvement in the bone differentiation of rat bone marrow cells can be achieved. We investigated the influence of materials modified with this treatment in vivo, on implanted surrounding tissues using polychrome sequential fluorescent labeling and micro-computer tomography scanning. NANOZR implant screws in the alkali-treated group and the untreated group were evaluated after implantation in the femur of Sprague–Dawley male rats, indicating that the amount of new bone in the alkali-modified NANOZR was higher than that of unmodified NANOZR. Alkali-modified NANOZR implants proved to be useful for the creation of new implant materials.

Effects of Plasma Treatment on the Bioactivity of Alkali-Treated Ceria-Stabilised Zirconia/Alumina Nanocomposite (NANOZR)

“…Previous studies have shown that there is not always a correlation between a decrease in carbon content on a material surface and a decrease in the contact angle [ 64 ]. In our previous study, XPS analysis revealed that it was possible to form hydroxyl groups on the nano-ZR surface with concentrated alkali treatment [ 37 , 38 ]. The present study shows that the combination of carbon decomposition on the material surface by atmospheric pressure plasma treatment imparts superhydrophilicity to the material surface.…”

“…It is presumed that the carbon decomposition effect on the nano-ZR surface and the introduction of hydroxyl groups exerted superhydrophilicity. Our previous study showed that treatment of nano-ZR with a concentrated alkali solution changes the zeta potential of the material surface from negative to positive [ 38 ]. Choi et al also revealed that application of atmospheric pressure plasma treatment to the implant material surface could render the zeta potential of the material surface positive [ 64 ].…”

“…According to our past report, various cells after 24 h of culture were stained and observed [ 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ].…”

“…We have shown that alkali-modified nano-ZR can accelerate osseointegration both in vitro and in vivo. Alkali-modified nano-ZR helps improve early adhesion and differentiation of rat bone marrow mesenchymal stem cells compared with unmodified nano-ZR surfaces [ 37 , 38 ]. These results suggest that alkali-modified nano-ZR is useful as a novel implant material, similar to the previously reported use of alkali-modified titanium [ 37 ].…”

“…These results suggest that alkali-modified nano-ZR is useful as a novel implant material, similar to the previously reported use of alkali-modified titanium [ 37 ]. Our latest study has also shown that alkali-modified nano-ZR treatment is effective for peri-implant hard-tissue formation [ 37 , 38 ]. However, compared to the biocompatibility of titanium surfaces with controlled nanostructures, the biocompatibility of alkali-treated nano-ZR is insufficient, and therefore development of new surface treatments is needed.…”