A PRELIMINARY INVESTIGATION OF POROUS TITANIUM / 解放军医学杂志

ABSTRACT

Porous titanium is a kind of new biomaterial. After being implanted into the bone, the ingrowth of the bone was demonstrated. This ingrowth of bone tissuse was thought to be beneficial to fixation of a prosthesis and filling of a bone cavity.In this study, the porous sample was abtained from sintered amorphous titanium powder, with the mean size of pores larger than 150? in diameter, and the porosity in the range of 45-47%. It was implanted into the femurs of rabbits and dogs, and specimons were taken for examination 2, 4, 6 and 12 weeks after operation.It was shown that the shear strength of the samples at the implant bone surface was 7.51kg/cm2 2 weeks after surgery. It was demonstrated that bone tissue had begun to grow into the meshwork 2 weeks after surgery, and deeper penetration was seen after 4 weeks. Scanning electron microscopy was done to show the appearance of bony growth into the meshwork. Bony growth was verified by x-ray diffraction scan analysis for calcium. Bone ingrowth could be seen in the majority of the interstices of the meshwork 12 weeks after surgery. Bone lacuna and tubules could be seen when stained with silver nitrate. The deepest penetration of bone ingrowth was 1400?. There was no obvious tissue reaction or formation of fibrous membrane.The use of the porous material may help to prevent loosening of a prosthesis. It is believed that porous titanium we used possesses the characteristics that a porous material should possess. Further research should be done to ascertain its clinical usefulness.