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The FSCM allows excellent cell growth, is not immunogenic and is well-tolerated in the cornea, and thus meets the basic criteria to serve as a scaffold to reconstitute the cornea.

Tissue engineering is a new approach to articular cartilage repair; however, the integration of the engineered cartilage into the host subchondral bone is a major problem in osteochondral injury. The aim of the present work, therefore, was to make a tissue-engineered osteochondral construct from a novel biphasic scaffold in a newly designed double-chamber bioreactor. This bioreactor was designed to coculture chondrocytes and osteoblasts simultaneously. The aim of this study was to prove that engineered cartilage could be formed with the use of this biphasic scaffold. The scaffold was constructed from gelatin and a calcium-phosphate block made from calcined bovine bone. The cartilage part of the scaffold had a uniform pore size of about 180 microm and approximate porosity of 75%, with the trabecular pattern preserved in the bony part of the scaffold. The biphasic scaffolds were seeded with porcine chondrocytes and cultured in a double-chamber bioreactor for 2 or 4 weeks. The chondrocytes were homogeneously distributed in the gelatin part of the scaffold, and secretion of the extracellular matrix was demonstrated histologically. The chondrocytes retained their phenotype after 4 weeks of culture, as proven immunohistochemically. After 4 weeks of culture, hyaline-like cartilage with lacuna formation could be clearly seen in the gelatin scaffold on the surface of the calcium phosphate. The results show that this biphasic scaffold can support cartilage formation on a calcium-phosphate surface in a double-chamber bioreactor, and it seems reasonable to suggest that there is potential for further application in osteochondral tissue engineering.

The diffusional reaction between titanium and zirconia was carried out isothermally at 1550°C in argon. The distinct reaction layers in the reaction‐affected zone between Ti and ZrO2 were investigated using analytical scanning electron microscopy, analytical transmission electron microscopy, and electron probe microanalyses. In the metal side, there existed five reaction layers in a sequence of α‐Ti(O), Ti2ZrO+α‐Ti(O, Zr), Ti2ZrO+α‐Ti(O, Zr)+β′‐Ti (O, Zr), α‐Ti (O, Zr)+β′‐Ti (O, Zr), and β′‐Ti (Zr, O) after cooling. In the zirconia side, two reaction layers were found: near the original interface, β′‐Ti coexisted with fine spherical c‐ZrO2−x and Chinese‐script‐like c‐ZrO2−x, which dissolved a significant amount of Y2O3 in solid solution; further away from the original interface, the coarsened intergranular α‐Zr was excluded from metastable ZrO2−x, resulting in the lenticular t‐ZrO2−x and ordered c‐ZrO2−x. An attempt was made to determine and propose the microstructural evolution and formation mechanism of the reaction layers between titanium and zirconia isothermally annealed at 1550°C.