A low-temperature biomimetic calcium phosphate surface enhances early implant fixation in a rat model.
The present study demonstrates increased early mechanical fixation of titanium implants coated with a new biomimetic apatite surface in a rat model. Male Sprague-Dawley rats received unilateral femoral medullary implants for periods of 1-4 weeks. The strength of fixation of the implant to the host bone increased more rapidly in the group receiving apatite-treated implants compared with the control group as evidenced by the apatite group's 21-fold greater fixation strength at 1 week (p = 0.009), 4-fold greater fixation strength at 2 weeks (p = 0.041), and 2-fold greater fixation strength at 4 weeks (p = 0.093) compared with the control. Fixation strength was correlated with bone-implant contact as determined from micro computed tomography assessment of the specimens (r2 = 0.338, p = 0.011 in the control group and r2 = 0.543, p < 0.001 in the apatite group). Furthermore, for a given amount of bone-implant contact, the fixation strength was higher in the apatite group than in the control group (p = 0.011), suggesting that the bone formed a stronger bond to the apatite coating than to the titanium. This difference in bonding strength accounted for the difference in mechanical behavior.
Kuroda
S
S
Department of Anatomy and Cell Biology, Rush University Medical Center, Chicago, Illinois 60612, USA.
Virdi
A S
AS
Li
P
P
Healy
K E
KE
Sumner
D R
DR
D000818:Animals; D040761:Biomimetic Materials / Q000494:pharmacology*; D002130:Calcium Phosphates / Q000494:pharmacology*; D020099:Coated Materials, Biocompatible; D005269:Femur / Q000000981:diagnostic imaging / Q000254:growth & development; D008297:Male; D019736:Prostheses and Implants; D051381:Rats; D017207:Rats, Sprague-Dawley; D013314:Stress, Mechanical; D013696:Temperature; D014057:Tomography, X-Ray Computed
D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; C020243:calcium phosphate