Evaluation of a novel nanocrystalline hydroxyapatite paste Ostim(® )in comparison to Alpha-BSM(® )- more bone ingrowth inside the implanted material with Ostim(® )compared to Alpha BSM(®)

BACKGROUND: The purpose of this study was to evaluate the performance a newly developed nanocrystalline hydroxyapatite, OSTIM(® )following functional implantation in femoral sites in thirty-eight sheep for 1, 2 or 3 months. Ostim(® )35 was compared to an established calcium phosphate, Alpha BSM(®). METHODS: Biomechanical testing, μ-CT analysis, histological and histomorphological analyses were conducted to compare the treatments including evaluation of bone regeneration level, material degradation, implant biomechanical characteristics. RESULTS: The micro-computed tomography (μCT) analysis and macroscopic observations showed that Ostim(® )seemed to diffuse easily particularly when the defects were created in a cancellous bone area. Alpha BSM(® )remained in the defect. The performance of Ostim was good in terms of mechanical properties that were similar to Alpha BSM(® )and the histological analysis showed that the bone regeneration was better with Ostim(® )than with Alpha BSM(®). The histomorphometric analysis confirmed the qualitative analysis and showed more bone ingrowth inside the implanted material with Ostim(® )when compared to Alpha BSM (® )at all time points. CONCLUSIONS: The successful bone healing with osseous consolidation verifies the importance of the nanocrystalline hydroxyapatite in the treatment of metaphyseal osseous volume defects in the metaphyseal spongiosa.