BIOACTIVE GLASS VERSUS HYDROXYLAPATITE IN RECONSTRUCTION OF OSTEOCHONDRAL DEFECTS IN THE RABBIT

We studied osseointegration of a bioactive glass (BG) and hydroxylapat ite (HA) in rabbit femur epiphyseal and metaphyseal regions. 17 BG and 24 HA cones implanted in defects through arthrotomy were analyzed. Th e holes for implants were drilled through distal femur joint surfaces. The cartilage wound repaired generally by fibrous tissue. Histomorpho metry showed that 61, 78, and 79 percent of BG surface was covered by bone at 3, 6, and 12 weeks, respectively. The corresponding figures fo r HA were 47, 67, and 78 percent. Chemical bonding between bone and im plants of both types was confirmed by scanning electron microscopy (SE M) and energy-dispersive x-ray analysis (EDXA). Formation of a calcium phosphaterich layer on the surface BG implant was demonstrated by EDX A. Our results indicate that the osseointegration rate of bioactive gl ass does not differ from that of hydroxylapatite.