BaTiO3 optimized 3Y-TZP ceramic with improved osteoblasts growth and enhanced osteogenic activity

Abstract Bioceramics for hard tissue repair in the fields of dentistry or orthopedics should have the ability to promote adhesion, proliferation and differentiation of osteoblast cells. In this study, different BaTiO3 (BT) ratio modified 3 mol% yttria stabilized tetragonal zirconia polycrystals (3Y-TZP) discs were prepared by conventional sintering. The specimen surfaces were characterized using scanning electron microscopy (SEM). The wettability of the material surface was measured by the water contact angle. Human osteoblastic cells (MG63) were used for the in vitro experiments. The cytotoxicity of the material was detected by the MTT assay. Cell morphology on the material surface was observed by SEM. The expression of alkaline phosphatase (ALP), and the expression of osteogenic associated genes such as runt-related transcription factor 2 (RUNX2), transforming growth factor beta (TGF-β), bone morphogenetic protein 4 (BMP4) and osteocalcin (OCN) were assessed to detect the osteogenic potential of the ceramic composites. Results showed that the BT ratio influenced the surface porosities of the ceramics. The 5 mol% BT/3Y-TZP group had a higher density and lower open porosity than 3 mol% and 7 mol% BT/3Y-TZP. The different surface porosities further affect the hydrophilicity of the surface. In comparison with the other groups, 5 mol% BT/3Y-TZP ceramic composite also had a significantly lower water contact angle, which demonstrated a superior hydrophilicity of the surface. A fine biocompatibility of the BT/3Y-TZP ceramic composites was confirmed by the MTT assay and cell morphology observations. Both the ALP assay and key osteogenic markers showed the 5 mol% BT/3Y-TZP group significantly promoted the osteogenic differentiation of osteoblasts, indicating that the 5 mol% BT optimized 3Y-TZP ceramics is a prospective candidate to be used in hard tissue repair due to its effective osteogenic properties and biocompatibility.