OBJECTIVEThis work aims to investigate the effect of porous tantalum and porous titanium on osseointegration.

METHODSTwo kinds of porous materials with same microporous parameters, namely, porous tantalum and porous titanium, were fabricated by computer-aided design (CAD) modeling and 3D printing technology. A defect model was established in 24 New Zealand white rabbits in the bilateral femoral lateral malleolus at the left and right side of each animal. Then, animals were randomly divided into two groups, and bone defects were repaired by porous tantalum and porous titanium (experimental and control groups, respectively). Animals were sacrificed at two, four, and eight weeks after implantation. Gross observation and methylene blue-acid fuchsin staining were used to observe osseointegration of the implant and bone interface, and the osseointegration strength of implant bone interface was tested by push-out test.

RESULTSAt two, four, and eight weeks after operation, the new bone tissue in the two groups increased gradually, and new bone trabecula appeared and grew into the pores of the materials. No significant difference (P>0.05) in osteogenesis and the strength of implant bone tissue interface between the two groups was observed.

CONCLUSIONS3D
printed porous tantalum implants, which exhibit comparable osseointegration capabilities to porous titanium implants, can form an early biological combination with bone tissue.