The Effect of Whitlockite as an Osteoconductive Synthetic Bone Substitute Material in Animal Bony Defect Model

Abstract

This study aimed to evaluate the biomechanical properties in vitro and the bone regeneration of whitlockite (WH) compared with hydroxyapatite (HA) or β-tricalcium phosphate (β-TCP)-based material. We investigated the morphology and phase composition of the bone grafts using a scanning electron microscope and X-ray diffractometer patterns and tested the compressive strength. Four circular defects of 8 mm in diameter were created on the calvaria of twelve rabbits. One defect was left empty, and each of the other defects was filled with WH, HA, and β-TCP. At 4 and 8 weeks, the specimens were harvested to evaluate for the new bone formation and the remaining bone grafts. Regarding the biomechanical properties, the three grafts had a similar micropore size, and WH showed nanopores. The compressive strength of WH was higher than HA and β-TCP without statistical significance. The radiological and histomorphometric analyses demonstrated that the new bone formation was similar among the groups. The remaining bone graft of the WH group was greater than that of the HA and β-TCP groups at 4 weeks (p < 0.05), and the total bone area of the WH, HA, and β-TCP groups was greater than that of the other (p < 0.01). WH has excellent volumetric stability and osteoconductivity compared with HA and β-TCP.

Review of Physical, Mechanical, and Biological Characteristics of 3D-Printed Bioceramic Scaffolds for Bone Tissue Engineering Applications

“…The fatigue strength of the scaffold is found by subjecting the scaffold to cyclic load . The porosity of the scaffold has a direct influence on cell proliferation and differentiation . Several studies were conducted to find the optimum pore size for the microporous interconnected scaffold structure.…”

“…The release of dipyridamole and BMP-2 increased the bone repair and regeneration . The ionic releases from the metal oxides, especially Mg 2+ and Si 2+ , are known to induce bone formation and vascularization in Hap scaffolds. , Vazquez et al. fabricated a microporous silica doped Hap scaffold using by the robocasting technique.…”

“…60 The porosity of the scaffold has a direct influence on cell proliferation and differentiation. 61 Several studies were conducted to find the optimum pore size When the pore size is greater than 400 μm, it provides better osteogenesis in in vitro and in vivo studies. 62 The mechanical properties of various bioceramic materials and their composites obtained for the different additive manufacturing techniques are given in Table 3.…”

“…249 The ionic releases from the metal oxides, especially Mg 2+ and Si 2+ , are known to induce bone formation and vascularization in Hap scaffolds. 61,250 Vazquez et al fabricated a microporous silica doped Hap scaffold using by the robocasting technique. The in vitro characterization shows the release of Si 2+ ions inducing blood vessel formation and enhancing the bioactivity after 5 days of incubation.…”

Enhancement of Anticorrosive Performance of Cardanol Based Polyurethane Coatings by Incorporating Magnetic Hydroxyapatite Nanoparticles

“…Previous reports are available on the use of hydroxyapatite (HAP) for bone tissue engineering, controlled drug delivery, and as filler for composites coatings. Even HAP modified with silver was used in the formulation of antibacterial composite coatings [ 33 ] as bone substitutes [ 34 ], drug and protein carriers [ 35 ], dental implants [ 36 ], etc. Additionally, magnetically modified HAP was utilized in the removal of heavy metals such as uranium (VI) [ 37 ], lead ion [ 38 ], cadmium (II) [ 39 ], copper, nickel [ 40 ], and other pollutants for the water [ 41 ].…”