Histological and histomorphometric investigations on bone integration of rapidly resorbable calcium phosphate...

Resorbable ceramics can promote the bony integration of implants. Their rate of degradation should ideally be synchronized with bone regeneration. We report here the results of a histological study of implants with two resorbable calcium phosphate ceramic coatings: Ca(2)KNa(PO(4))(2)-(GB14) and Ca(10)[K/Na](PO(4))(7)-(602020). The results attained with these ceramic-coated implants show the benefits of these materials with regard to bioactive bone-healing stimulation, compared with uncoated implants. The GB14 ceramic coating exhibited greater bone regeneration and differentiation on its surface than the conventional hydroxyapatite coating and helped bone tissue achieve more extensive contact free of connective tissue. Not until the coating disintegrated did the histological features of GB14- and 602020-coated implants converge-both implant types were integrated into bone. Rapid disintegration of the coating material, as with 602020, supports osteoblast proliferation but has negative effects on bone mineralization. Both resorbable ceramics tested, GB14 and 602020, demonstrated bioactivity; even metal surfaces coated with these materials were populated by mature bone tissue without connective tissue after disintegration of their ceramic coating. The less rapidly degrading material, GB14, achieved better results. Degradable calcium phosphate coatings have the potential to stimulate bone regeneration. From the histological viewpoint, the resorbable ceramics examined here can be recommended as coating materials for clinical use.