Effect on growth and osteoblast mineralization of hydroxyapatite-zirconia (HA-ZrO ₂ ) obtained by a new low temperature system

Abstract

Ceramics and bioceramics, such as hydroxyapatite and zirconium, are used in bone tissue engineering. Hydroxyapatite has chemical properties similar to bone while zirconium offers suitable mechanical properties. The aim of this article is to evaluate the ability to support cell growth and osteoblastic mineralization of hydroxyapatite-zirconium obtained by a new system based on different low temperatures, such as 873 K (HZ600), 923 K (HZ650) and 973 K (HZ700). Hydroxyapatite-zirconia obtained by this new system was examined in terms of thermogravimetric features and x-ray diffractograms. Furthermore, the ability for supporting osteoblast growth and mineralization were analyzed. By x-ray diffraction analysis, we clearly demonstrated that no high-temperature processing was required. Moreover, it is possible to form tetragonal-zirconium at 923 K. Proliferation assays showed that osteoblast growth was not influenced by any of the composite evaluated. Regarding the osteogenic marker Col1, a 2-fold increase in expression was observed for HZ650 compared to HZ600 and HZ700. Interestingly, osteoblasts grown on HZ650 showed globular accretions covered with collagen bundles and calcium-rich extracellular matrix whereas HZ600 and HZ700 showed no phosphate or calcium deposits. This study demonstrated that at 923 K it is possible to generate stable tetragonal-zirconium and the resulting HZ650 composite is able to promote a suitable osteoblast mineralization process.

Effect of calcium glucoheptonate on proliferation and osteogenesis of osteoblast-like cells in vitro

“…Elevated calcium concentrations at the resorptive sites of bone can also regulate osteoblast functions [45]. Accumulation of calcium in the extracellular space and its organization into hydroxyapatite crystals is a key marker of osteoblast maturation [46].…”

In Vitro Ortamda Kalsiyum Klorürün Osteoblast Benzeri Hücreler Üzerine Etkisi

“…The answer to why calcium salts in sufficient concentration yield good results in terms of supporting proliferation and maturation of osteoblast like cells, lies in the accumulation of calcium in the extracellular space. It is inevitable binding to hydroxyapatite crystals, in fact is a key factor in supporting and maturing osteoblast like cells (Bermudez-Reyes et al 2018).…”

Nanomaterials-Upconverted Hydroxyapatite for Bone Tissue Engineering and a Platform for Drug Delivery

“… 30 The M-phase is feeble at room temperature, therefore, to prevent the T-phase from being converted to M-phase, a stabilization process is needed. 7 …”

“…30 The M-phase is feeble at room temperature, therefore, to prevent the T-phase from being converted to M-phase, a stabilization process is needed. 7 Zirconia has a macroporous structure that gives it mechanical strength about seven times greater than hydroxyapatite. Therefore several efforts of research have been conducted in the coating of zirconia on hydroxyapatite surface to combine the bioactive properties of hydroxyapatite and mechanical strength of zirconia to produce a better structure and character of calcium phosphate composite for biomedical applications.…”