THE BONDING BEHAVIOR OF DP-BIOGLASS AND BONE TISSUE

There are many reports on the surface reactions of surface-active cera mics. A Ca-P-rich layer was found on the surface of these bioactive ce ramics implanted in bone tissue, a chemical bond having been establish ed between the mineralized matrix of the bone and the apatite layer of the bioactive ceramic. It has been reported that the direct bonding o f bone to DP-Bioglass was due to the deposition and subsequent mineral ization of organic bone matrix at the outer layer of the implant. Thus the strength of the bonding of DP-Bioglass with bone structure is exp ected to be such that it will overcome the fixing problems of joint re placement and improve the long-term performance of prostheses if the b ioactive glass is coated onto alloys or stainless steel. In this study , DP-Bioglass was pressed into a steel disc, 6 mm in diameter and 5 mm thick, under a hydrostatic pressure of 270 MPa, and then sintered at 810 degrees C for 2 hours. The DP-Bioglass discs were implanted into t he condyle area of mature male rabbits for 2, 4, 8, 16 and 32 weeks. T he failure load, when an implant detached from the bone or when the bo ne itself broke, was measured by a push-out test. Sintered hydroxyapat ite bioceramic was used in a control group and the results were compar ed with those using DP-Bioglass. The histological evaluation and histo morphometric investigation are described in the study to demonstrate t he bonding behavior between DP-Bioglass and bone tissue.