Biocompatibility of calcium phosphate bone cement with optimized mechanical properties

Abstract

The broad aim of this work was to investigate and optimize the properties of calcium phosphate bone cements (CPCs) for use in vertebroplasty to achieve effective primary fixation of spinal fractures. The incorporation of collagen, both bovine and from a marine sponge (Chondrosia reniformis), into a CPC was investigated. The biological properties of the CPC and collagen–CPC composites were assessed in vitro through the use of human bone marrow stromal cells. Cytotoxicity, proliferation, and osteoblastic differentiation were evaluated using lactate dehydrogenase, PicoGreen, and alkaline phosphatase activity assays, respectively. The addition of both types of collagen resulted in an increase in cytotoxicity, albeit not to a clinically relevant level. Cellular proliferation after 1, 7, and 14 days was unchanged. The osteogenic potential of the CPC was reduced through the addition of bovine collagen but remained unchanged in the case of the marine collagen. These findings, coupled with previous work showing that incorporation of marine collagen in this way can improve the physical properties of CPCs, suggest that such a composite may offer an alternative to CPCs in applications where low setting times and higher mechanical stability are important. © 2015 The Authors. Journal of Biomedical Materials Research Part B: Applied Biomaterials Published by Wiley Periodicals, Inc. 104B:308–315, 2015.

Biocompatibility of calcium phosphate bone cement with optimised mechanical properties: an in vivo study

“…This finding is in line with the results of previous in vitro work showing that cells were able to proliferate equally well on all of the CPCs as well as differentiating on both α -TCP-CPC and MC-CPC, albeit at shorter time points [24]. …”

“…α -TCP-CPC was produced following a previously described protocol [24] and shaped using polytetrafluoroethylene (PTFE) moulds. Conical cement samples, 8 mm high with a base diameter of 4 mm (Fig.…”

“…Similar methods, also described by Palmer et al [24], were used to produce the Collagen-CPC composites. Briefly, bovine derived collagen (Sigma-Aldrich, Gillingham, UK) or collagen extracted from C. reniformis (KliniPharm GmbH, Frankfurt, Germany) was incorporated into α -TCP-CPC at a loading of 1 wt% to form composites referred to as BC-CPC and MC-CPC respectively.…”

“…Earlier work investigating both bovine collagen and collagen extracted from the marine Demosponge Chondrosia reniformis (Nardo, 1847 [19]) has shown that mechanical and handling properties of a novel CPC formulated from 100 % α -tricalcium phosphate ( α -TCP-CPC) can meet several of the clinical requirements for PV through collagen incorporation (Table 1) [20–23], without compromising in vitro biological performance [24]. C. reniformis has been identified worldwide, has a high collagen content [25] and a low risk of detrimental toxic compounds [26].…”

In vitro Growth Pattern of Primary Human Osteoblasts on Calcium Phosphate- and Polymethylmethacrylate-Based Bone Cement

“…However, Palmer et al [23] also showed an increased cytotoxicity of their tested Ca-P cement-collagen composites in vitro. However, compared to other commonly used biomaterials, they found the level of cytotoxicity in their study to be lower, concluding it not likely to be clinically relevant.…”