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PurposeThe physicochemical properties of a xenograft are very important because they strongly influence the bone regeneration capabilities of the graft material. Even though porcine xenografts have many advantages, only a few porcine xenografts are commercially available, and most of their physicochemical characteristics have yet to be reported. Thus, in this work we aimed to investigate the physicochemical characteristics of a porcine bone grafting material and compare them with those of 2 commercially available bovine xenografts to assess the potential of xenogenic porcine bone graft materials for dental applications.MethodsWe used various characterization techniques, such as scanning electron microscopy, the Brunauer-Emmett-Teller adsorption method, atomic force microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction, and others, to compare the physicochemical properties of xenografts of different origins.ResultsThe porcine bone grafting material had relatively high porosity (78.4%) and a large average specific surface area (SSA; 69.9 m2/g), with high surface roughness (10-point average roughness, 4.47 µm) and sub-100-nm hydroxyapatite crystals on the surface. Moreover, this material presented a significant fraction of sub-100-nm pores, with negligible amounts of residual organic substances. Apart from some minor differences, the overall characteristics of the porcine bone grafting material were very similar to those of one of the bovine bone grafting material. However, many of these morphostructural properties were significantly different from the other bovine bone grafting material, which exhibited relatively smooth surface morphology with a porosity of 62.0% and an average SSA of 0.5 m2/g.ConclusionsConsidering that both bovine bone grafting materials have been successfully used in oral surgery applications in the last few decades, this work shows that the porcine-derived grafting material possesses most of the key physiochemical characteristics required for its application as a highly efficient xenograft material for bone replacement.

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Novel bioactive and biodegradable glass ceramics with high mechanical strength in the (50-x/2)CaO ⅐ SiO 2 OxB 2 O 3 (4.2 Յ x Յ 17.2) system were investigated. The systems consisted of three phases: monoclinic wollastonite, calcium metaborate, and amorphous borosilicate matrix. The glass ceramics containing 4.2 mol% and 8.4 mol% B 2 O 3 showed high bulk density and a dense microstructure. Mechanical strengths of the glass ceramics were higher than those of other bioactive ceramics: high compressive strength (2813 MPa), bending strength of 212 MPa, and fracture toughness of 3.12 MPa ⅐ m 1/2 . The glass-ceramic formed apatite layer on their surface in the simulated body fluid and showed significant biodegradation. The degree of apatite formation in the glass ceramics depended on the calcium metaborate content and borosilicate glassy matrix. Additional calcium metaborate and borosilicate glassy matrix increased the apatite formation rate on the surface. It might be likely that calcium metaborate causes supersaturation of Ca ions, for its high solubility in SBF and the water-reactive borosilicate glassy matrix formed SiOOH groups on the surface to provide nucleation sites for apatite formation. Also, through in vitro test for the biocompatibility of the CaOOSiO 2 OB 2 O 3 glass ceramics, no cytotoxicity of the glass ceramics were found. The results on bioactivity and noncytotoxicity indicated that glass ceramics in the (50-x/ 2)CaO ⅐ SiO 2 OxB 2 O 3 (4.2 Յ x Յ 17.2) system could be useful as a biodegradable bone replacement material.