[Results of application of hydroxyapatite and hydroxyapatitecollagen.]

The authors present their experience of the application of hydroxyapatite and a composite-hydroxyapatitecollagen in 2 groups of patients. In the first group they evaluate the mediumterm results in 10 girls and 8 boys of average age of 12,5 years after the filling of bone defects in case of bone cysts, aneurysmatic cysts, fibrous cortical defect and eosinophilous granuloma. Hydroxyapatite was applied in the form of rolls, small bricks, strips. The first signs of healing were evident as early as after 4 months, after 36 months osteointegration was practically finished. In the second group of 1995-2000 period they applied hydroxyapatite in 15 patients of average age of 45 years. In this group they applied the mentioned biomaterial also in 6 patients with instabilities and primary and secondary (metastasis) bone tumours on the spine where they also achieved after a shorter follow-up of 6-8 months good osteoinductive and conductive qualities of the biomaterial. The authors point out the two biggest contributions in this respect: filling of bone cavities with an unusually big amount of hydroxyapatite (up to 70 g) and good, even though only short-term results after resection and filling of malignant bone tumours. Key words: hydroxyapatite, collagen, osteoinduction, osteoconduction, bone defects.