Influence of alumina substrates open porosity on calcium phosphates formation produced by the biomimetic method

Impact of ZrO2 Content on the Formation of Sr-Enriched Phosphates in Al2O3/ZrO2 Nanocomposites for Bone Tissue Engineering

This study investigates the profound impact of the ZrO2 inclusion volume on the characteristics of Al2O3/ZrO2 nanocomposites, particularly influencing the formation of calcium phosphates on the surface. This research, aimed at advancing tissue engineering, prepared nanocomposites with 5, 10, and 15 vol% ZrO2, subjecting them to chemical surface treatment for enhanced calcium phosphate deposition sites. Biomimetic coating with Sr-enriched simulated body fluid (SBF) further enhanced the bioactivity of nanocomposites. While the ZrO2 concentration heightened the oxygen availability on nanocomposite surfaces, the quantity of Sr-containing phosphate was comparatively less influenced than the formation of calcium phosphate phases. Notably, the coated nanocomposites exhibited a high cell viability and no toxicity, signifying their potential in bone tissue engineering. Overall, these findings contribute to the development of regenerative biomaterials, holding promise for enhancing bone regeneration therapies.

Effect of calcium phosphate/bovine serum albumin coated Al2O3-Ti biocomposites on osteoblast response

OBJECTIVES

The biological performance of aluminum oxide-titanium (Al2O3-Ti) composites requires special attention to achieve improved osteoblastic differentiation, and subsequent osseointegration/strong anchorage with the surrounding bone. Therefore, the aim of this study was to improve them by providing calcium phosphate (Ca-P)/bovine serum albumin (BSA) coating on their surfaces.

METHODS

Ca-P)/BSA coatings were prepared on the surfaces of 75vol.%Ti composites (75Ti-BSA) and pure Ti (100Ti-BSA as a control). The surface characteristics, phase analysis, micro-hardness, BSA release profile and biological responses including cytotoxicity, cell viability, differentiation, mineralization, and cell adhesion were evaluated.

RESULTS

The results showed that lower cytotoxicity% and higher mitochondrial activity or viability % were associated with the samples with Ca-P/BSA coatings (particularly 75Ti-BSA having 21.3% cytotoxicity, 111.4% and 288.6% viability at day 1 and 7, respectively). Furthermore, the Ca-P/BSA coating could highly enhance the differentiation of pre-osteoblast cells into osteoblasts in 75Ti-BSA group (ALP concentration of 4.8 ng/ml). However, its influence on cell differentiation in 100Ti-BSA group was negligible. Similar results were also obtained from mineralization assay. The results on cell adhesion revealed that the Ca-P/BSA coated samples differently interacted with MC3T3-E1 cells; enlarged flat cells on 75Ti-BSA vs more spindle-shaped cells on 100Ti-BSA.

CONCLUSIONS

Ca-P/BSA coated Al2O3-Ti provided promising biological performance, superior to that of uncoated composites. Therefore, they have the potential to improve implant osseointegration.

Ceramic Materials for Biomedical Applications: An Overview on Properties and Fabrication Processes

A growing interest in creating advanced biomaterials with specific physical and chemical properties is currently being observed. These high-standard materials must be capable to integrate into biological environments such as the oral cavity or other anatomical regions in the human body. Given these requirements, ceramic biomaterials offer a feasible solution in terms of mechanical strength, biological functionality, and biocompatibility. In this review, the fundamental physical, chemical, and mechanical properties of the main ceramic biomaterials and ceramic nanocomposites are drawn, along with some primary related applications in biomedical fields, such as orthopedics, dentistry, and regenerative medicine. Furthermore, an in-depth focus on bone-tissue engineering and biomimetic ceramic scaffold design and fabrication is presented.