THE MINI BOTTLE BRUSH - A NEW FASTENING DEVICE IN CANCELLOUS BONE

A new design for bone implants, the bottle brush, was recently present ed in a pilot study on marrow cavities in the femur of rabbits. In thi s study, the concept is further evaluated on a mini bottle brush. The fixture, 5x7 mm, with an implant shaft made of CP-titanium and bristle s of nylon coated with sputtered titanium, was inserted into the cance llous bone of the medial femoral condyle in 15 adult rabbits. The tita nium fixture was compared with a similar brush without the titanium sp uttered surface. The animals were sacrificed after 4 months and the qu antity and quality of bone integration were evaluated with pull-out te sts and histological examination. In both parameters, the values were significantly higher for the titanium-sputtered brushes, with removal forces similar to titanium cylinders of the same size and with a bone- to-metal contact area of about 50%.