The fabrication and biochemical evaluation of alumina reinforced calcium phosphate porous implants.
Alumina reinforced calcium phosphate porous implants were manufactured to improve the mechanical strength while maintaining the bioactivity of calcium phosphate ceramics. The alumina porous bodies, which provided the mechanical strength, were fabricated by a polyurethane sponge method and multiple coating techniques resulted in the porous bodies with a 90-75% porosity and a compressive strength of up to approximately 6MPa. The coating of hydroxyapatite (HAp) or tricalcium phosphate (beta-TCP) was performed by dipping the alumina porous bodies into calcium phosphate ceramic slurries and sintering the specimens. The fairly strong bonding between the HAp or TCP coating layer and the alumina substrate was obtained by repeating the coating and sintering processes. The biochemical evaluations of the porous implants were conducted by in vitro and in vivo tests. For in vitro test, the implants were immersed in Ringer's solution and the release of Ca and P ions were detected and compared with those of calcium phosphate powders. For in vivo test, the porous bodies were implanted into mixed breed dogs and bone mineral density measurements and histological studies were conducted. The alumina reinforced HAp porous implants had a higher strength than the HAp porous implants and exhibited a similar bioactivity and osteoconduction property to the HAp porous implants.
Jun
Youn Ki
YK
School of Materials Science and Engineering, Seoul National University, 151-742, Seoul, South Korea.
Kim
Wan Hee
WH
Kweon
Oh Kyeong
OK
Hong
Seong Hyeon
SH
D000537:Aluminum Oxide / Q000737:chemistry*; D000818:Animals; D015519:Bone Density; D002130:Calcium Phosphates / Q000737:chemistry*; D002516:Ceramics / Q000737:chemistry*; D004285:Dogs; D017886:Durapatite / Q000737:chemistry; D006801:Humans; D007477:Ions; D008855:Microscopy, Electron, Scanning; D011140:Polyurethanes / Q000737:chemistry; D019736:Prostheses and Implants; D013997:Time Factors; D014961:X-Ray Diffraction
D002130:Calcium Phosphates; D007477:Ions; D011140:Polyurethanes; C485828:alpha-tricalcium phosphate; C485817:beta-tricalcium phosphate; C485830:tetracalcium phosphate; C485838:calcium phosphate, monobasic, anhydrous; D017886:Durapatite; C020243:calcium phosphate; C018392:tricalcium phosphate; C485829:calcium phosphate, dibasic, anhydrous; D000537:Aluminum Oxide