BONE REPAIR OF DEFECTS FILLED WITH A PHOSPHOCALCIC HYDRAULIC CEMENT -AN IN-VIVO STUDY

A quickly setting calcium phosphate-based hydraulic cement mixed with particles of tricalcium phosphate (TCP) ceramic was implanted in 56 me taphysial defects made in the long bones of ten adult mongrel dogs. Mi croradiography, histology and scanning electron microscopy (SEM) demon strated the slow resorption of the cement and the bony incorporation o f the calcium phosphate ceramic particles which were consistently embe dded in bone. The original structural pattern of the bone tended to be restored 7 months after implantation. The cement did not hinder the i ncorporation of the calcium phosphate ceramic particles, neither did i t elicit any inflammatory or foreign-body response. The cement was eas ily shaped and allowed a perfect filling of any defect, resulting in c lose contact of the whole implant surface with the host bone at the ti me of surgery, associated with appreciable mechanical strength. Most o f the practical problems associated with the use of calcium phosphate ceramics in the repair of bone defects could be overcome with the ceme nt.