Tensile and torsional shear strength of the bone implant interface of titanium implants in the rabbit

The effect of three different titanium plasma flame spray coatings on the tensile strength and the effect of macrostructures on the torsional shear strength of the bone implant interface was studied. Titanium cylinders, of 8 mm length and 4 mm diameter, were implanted into distal rabbit femurs. For tensile testing, two porous titanium plasma flame spray coatings, Plasmapore^®, fine-grain Plasmapore^®, 1 dense, unporous coating, Plasmapore^® fine on cylinders with axial grooves, and corundum blasted specimens as control group were used. For torsional loading smooth, and macrostructured cylinders with axial grooves, both with Plasmapore^® fine-coating, were used. After 168 days the implant-bone interface was biomechanically tested. A tensile test and a torsional shear test was performed. The results indicated, that the titanium plasma flame spray coatings did not differ in their tensile interface strength, but yielded a stronger interface as sandblasted surfaces and that the macrostructures did not influence the torsional shear strength.