Evaluating the osseointegration of macroporous titanium alloy implants in rats

The studies of titanium and his alloys seek the quality improvement and time shortening in bone repair of metallic implants, solving problems as bone-implant interface, which may determine the clinical success. The powder metallurgy (PM) allows obtaining of samples in shape and dimensions at final state (Near-net Shape), avoiding the step of machining. Objectives: The aim of this study is to evaluate the macroporous implants osseointegration obtained through the PM method with gelatin added in rats. Methods: It was used as the control group, samples of commercially pure titanium (cpTi) and Ti-13Nb-13Zr alloy samples obtained by PM process, sintered in 1150°C/ 14 hours (10^-5 µBar). To obtaining of porous samples 15% of gelatin, weight proportion, were added to metallic powders (cpTi, Ti-13Nb-13Zr), the samples were thermally treated in a vacuum oven (10^-2 µBar) at 300°C/ 90 minutes and afterwards sintered in the same conditions of the control groups. Wistar rats, males, were used as the animal model with 3 animals per group. After 28 days period, the animals were sacrificed and bone-implant samples were taken for qualitative morphology analyses in optical microscopy (OM) and scanning electron microscopy (SEM). Results: The control samples were dense, while the gelatin added samples had approximately 40% of porosity. Through the morphological analysis was possible to observe the formation of bone on the surface of all the implants, moreover, in the macroporous implants was observed the presence of cells in the bone interconnected channels and pores. Conclusions: Obtaining metallic implants by the technic of PM with gelatin provide a favorable outcome to the growth of bone tissue in the pores and interconnected channels, conducing to a improved establishment of the implant in the bone, promoting a better rehabilitation. Acknowledgements: FAPESP 06/52700-2.