Improved bone ingrowth and fixation with a thin calcium phosphate coating intended for complete resorption.
Bonit is claimed to be a resorbable electrochemically deposited calcium phosphate coating consisting mainly of brushite, which is a hydroxyapatite precursor. This study involved a comparison of Ti6Al4V screw-shaped implants with and without a 15 +/- 5 microm Bonit coating in rabbit tibia and femur, after 6 and 12 weeks of insertion. The biomechanical removal torque test showed significantly increased values for the coated implants after 12 weeks (p < 0.05) but not after 6 weeks of integration. Higher bone-implant contact was found for the coated implants in the tibia after 6 weeks and for both tibial and femoral screws after 12 weeks (p < 0.05). There was no difference in the inflammatory reaction around the implants, and possible grains of the coating could be detected after 6 weeks, but not after 12 weeks of follow-up. This unloaded short-term study has shown promising results for the easily applicable and resorbable coat (Bonit) compared to uncoated titanium-alloy implants.
Reigstad
O
O
Orthopaedic Department, Rikshospitalet/National Hospital, 0027 Oslo, Norway. ole.reigstad@rikshospitalet.no
Franke-Stenport
V
V
Johansson
C B
CB
Wennerberg
A
A
Røkkum
M
M
Reigstad
A
A
D000497:Alloys; D000818:Animals; D002130:Calcium Phosphates / Q000737:chemistry / Q000378:metabolism*; D020099:Coated Materials, Biocompatible / Q000737:chemistry / Q000378:metabolism*; D017886:Durapatite / Q000737:chemistry / Q000378:metabolism; D005260:Female; D005269:Femur / Q000378:metabolism*; D020007:Implants, Experimental; D008422:Materials Testing; D016348:Osseointegration; D011817:Rabbits; D013314:Stress, Mechanical; D013499:Surface Properties; D013977:Tibia / Q000378:metabolism*; D014025:Titanium / Q000378:metabolism
D000497:Alloys; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; C031462:titanium alloy (TiAl6V4); D017886:Durapatite; C020243:calcium phosphate; D014025:Titanium; C494366:calcium phosphate, dibasic, dihydrate