In vitro and in vivo study of commercial calcium phosphate cement HydroSet™

Abstract

The commercial calcium phosphate cement, HydroSet™, was investigated in vitro, studying phase formation, compressive strength and setting time, followed by an ovine in vivo study to measure osseointegration, bone apposition and bone-to-graft contact. The X-ray diffraction and P Magic Angle Spinning Nuclear Magnetic Resonance (MAS NMR) results showed the initial formation of octacalcium phosphate and hydroxyapatite at one hour. Over 7 days the octacalcium phosphate transformed to apatite, which was the only crystalline phase of the cement at 28 days. This apatite phase is thought to be a calcium deficient apatite. In the scanning electron microscopy, histological images of 12-week ovine in vivo results showed a high degree of osseointegration, 92.5%. Compressive strength comparisons between in vitro and in vivo measurements showed a dramatic difference between the in vitro measurements (highest 25.4 MPa) and in vivo (95 MPa), attributed to bone ingrowth into the cement in vivo. To the best of our knowledge this is the first time phase evolution of HydroSet™ and the properties studied in vitro complement the in vivo evaluation of the cement in a publication. The significance of the new finding of initial formation of octacalcium phosphate in this cement is discussed. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 21-30, 2018.

Tailoring Biotribological Performance of Polytetrafluoroethylene Nanocomposites through Control of Diameters and Aspect Ratios of In Situ Filled Hydroxyapatite Nanowires

“…To identify HAP in the nanocomposites, 31 P MAS nuclear magnetic resonance (NMR) spectra of the HAP nanocomposites synthesized via different ethanol/water ratios were performed and are included in Figure S2, Supporting Information. The results showed that the chemical shift of 31 P in the nanocomposites is in line with that of the HAP reported in the literature, [49] indicating that HAP was successfully synthesized in the matrix PTFE despite a low concentration. The IR spectrum of the in situfabricated PTFE nanocomposite presented a stretching mode of physiosorbed water at 3705 cm À1 , which is an indication of an increase in hydrophilicity in comparison with the matrix PTFE and suggested the presence of the HAP in situ filled.…”

Graphene Oxide Finely Tunes the Bioactivity and Drug Delivery of Mesoporous ZnO Scaffolds

“…Hence, PO 4 3– and Ca 2+ ions combine together with more difficulty, and calcium phosphate formation is partially prevented. This also explains the formation of a phosphorous-rich apatite compound, as evident from chemical composition analyses (Ca/P ∼0.7), and which has been reported to be helpful in promoting in vivo osseointegration. − On the other hand, the negatively charged ZnO@GO surface is due to the intrinsic abundance of hydroxyl groups of GO and further promotes absorption of Ca 2+ ions from SBF solution. PO 4 3– are then attracted, and finally calcium phosphate compounds are formed.…”

Bioceramic Scaffolds

“…It has been reported by Kent et al in vitro and in vivo measurements of commercial calcium phosphate cement is considerably stronger in vivo compared to in vitro, the cause of this attributed to bone formation within the cement pores and a high degree of osseointegration [131]. Chen et al, 2013 proved that when hUCMSCs and hBMSCs were seeded onto a CPC scaffold.…”