Reinforcement of Calcium Phosphate Cement with E-Glass Fibre

Authors: Sudip Dasgupta, Debosmita Pani, Kanchan Maji

Abstract:

Calcium Phosphate Cement (CPC) due to its high bioactivity and optimum bioresorbability shows excellent bone regeneration capability. Despite it has limited applications as bone implant due to its macro-porous microstructure causing its poor mechanical strength. The reinforcement of apatitic CPCs with biocompatible fibre glass phase is an attractive area of research to improve upon its mechanical strength. Here, we study the setting behaviour of Si-doped and un-doped α tri calcium phosphate (α - TCP) based CPC and its reinforcement with addition of E-glass fibre. Alpha Tri calcium phosphate powders were prepared by solid state sintering of CaCO3 , CaHPO4 and Tetra Ethyl Ortho Silicate (TEOS) was used as silicon source to synthesize Si doped α-TCP powders. Both initial and final setting time of the developed cement was delayed because of Si addition. Crystalline phases of HA (JCPDS 9- 432), α-TCP (JCPDS 29-359) and β-TCP (JCPDS 9-169) were detected in the X-ray diffraction (XRD) pattern after immersion of CPC in simulated body fluid (SBF) for 0 hours to 10 days. As Si incorporation in the crystal lattice stabilized the TCP phase, Si doped CPC showed little slower rate of conversion into HA phase as compared to un-doped CPC. The SEM image of the microstructure of hardened CPC showed lower grain size of HA in un-doped CPC because of premature setting and faster hydrolysis of un-doped CPC in SBF as compared that in Si-doped CPC. Premature setting caused generation of micro and macro porosity in un-doped CPC structure which resulted in its lower mechanical strength as compared to that in Si-doped CPC. It was found that addition of 10 wt% of E-glass fibre into Si-doped α-TCP increased the average DTS of CPC from 8 MPa to 15 MPa as the fibres could resists the propagation of crack by deflecting the crack tip. Our study shows that biocompatible E-glass fibre in optimum proportion in CPC matrix can enhance the mechanical strength of CPC without affecting its biocompatibility. 

Keywords: Calcium phosphate cement, biocompatibility, e-glass fibre, diametral tensile strength.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1109119

References:

[1] Dorozhkin, S.V., 2008. “Calcium orthophosphate cements for biomedical application”. Journal of Materials Science 43, 3028–3057.
[2] Larsson, S., 2010. “Calcium phosphates: what is the evidence?”, Journal of Orthopaedic Trauma 24, 41–45.
[3] Morgan, E.F., Yetkinler, D.N., Constantz, B.R., Dauskardt, R.H., 1997. “Mechanical properties of carbonated apatite bone mineral substitute: strength, fracture and fatigue behavior”, J. Mater. Sci., Mater. Med. 8, 559–570.
[4] Ginebra, M.P., Espanol, M., Montufar, E.B., Perez, R.A., Mestres, G., 2010. “New processing approaches in calcium phosphate cements and their applications in regenerative medicine”, Acta Biomater. 6, 2863– 2873.
[5] Ginebra, M.P., Rilliard, A., Fernandez, E., Elvira, C., San Roman, J., Planell, J.A., 2001. “Mechanical and rheological improvement of a calcium phosphate cement by the addition of a polymeric drug”, J. Biomed. Mater. Res. 57, 113–118.
[6] Ishikawa, K., 2008. “Calcium phosphate cement”, In: Kokubo, T. (Ed.), Bioceramics and Their Clinical Applications. CRC Press, Woodhead Publishing Ltd., pp. 438–463.
[7] Lewis, G., 2006. “Injectable bone cements for use in vertebroplasty and kyphoplasty: State of the Art Review”, J. Biomed. Mater. Res. B 76, 456–468.
[8] Espanol, M., Perez, R.A., Montufar, E.B., Marichal, C., Sacco, A. Ginebra, M.P., 2009. “Intrinsic porosity of calcium phosphate cements and its significance for drug delivery and tissue engineering applications”, Acta Biomater. 5, 2752–2762.
[9] Martin, R.I., Brown, P.W., 1995. “Mechanical properties of hydroxyapatite formed at physiological temperature”, J. Mater. Sci., Mater. Med. 6, 138–143.
[10] Currey, J.D., Butler, G., 1975. “The mechanical properties of bone tissue in children”, J. Bone Joint Surg. A 57, 810–814.
[11] Morgan, E.F., Yetkinler, D.N., Constantz, B.R., Dauskardt, R.H., 1997. “Mechanical properties of carbonated apatite bone mineral substitute: strength, fracture and fatigue behavior”, J. Mater. Sci., Mater. Med. 8, 559–570.
[12] Nalla, R.K., Kinney, J.H., Ritchie, R.O., 2003. “Mechanistic fracture criteria for the failure of human cortical bone”, Nat. Mater. 2, 164–168.
[13] Callister Jr W.D., Rethwisch D.G. “Materials science and engineering: an introduction”, 7th ed, John Wiley Sons Inc; 2009.
[14] Hannant D.J., Hughes D.C., Kelly A. “Toughening of cement and other brittle solids with fibres”, Philosophical Transaction A 1983; 310: 175- 190.
[15] Xu, H.H.K., Quinn, J.B., 2002. “Calcium phosphate cement containing resorbable fibres for short-term reinforcement and macroporosity”, Biomaterials 23, 193–202.
[16] Xu, H.H.K., Quinn, J.B., Takagi, S., Chow, L.C., Eichmiller, F.C., 2001. “Strong and macroporous calcium phosphate cement: effects of porosity and fibre reinforcement”, J. Biomed. Mater. Res. 57A, 457–466.
[17] Xu, H.H.K., Carey, L.E., Burguera, E.F., 2007a. “Strong, macroporous, and in situ-setting calcium phosphate cement layered structures”, Biomaterials 28, 3786–3796.
[18] Zuo, Y., Yang, F., Wolke, J.G.C., Li, Y., Jansen, J.A., 2010. “Incorporation of biodegradable electrospun fibres into calcium phosphate cement for bone regeneration”, Acta Biomater. 6, 1238–1247.
[19] Kean-Khoon Chew, Kah-Ling Low, Sharif Hussein Sharif Zein, David S. McPhail, Lutz-Christian Gerhardt, Judith A. Roether, Aldo R. Boccaccini, “Reinforcement of calcium phosphate cement with multiwalled carbon nanotubes and bovine serum albumin for injectable bone substitute applications”, Journal of the Mechanical Behavior of Biomedical Materials, Volume 4, Issue 3, April 2011, Pages 331–339
[20] Dos Santos, L.A., de Oliveira, L.C., da Silva Rigo, E.C., Garcia Carrodéguas, R., Ortega Boschi, A., Fonseca de Arruda, A.C., 2000. “Fibre reinforced calcium phosphate cement”, Artif. Organs 24 (3), 212– 216.
[21] Xu, H.H.K., Eichmiller, F.C., Giuseppetti, A.A., 2000. “Reinforcement of a self-setting calcium phosphate cement with different fibres”, J. Biomed. Mater. Res. 52, 107–114.
[22] T. Kokubo, H. Kushitani, S. Sakka, T. Kitsugi and T. Yamamuro, "Solutions able to reproduce in vivo surface-structure changes in bioactive glass-ceramic A-W", J. Biomed. Mater. Res., 24, 721-734 (1990).
[23] Ginebra, M.P., E. Fernández, E.A.P. De MaeyerR.M.H. Verbeeck, M.G. Boltong, J. Ginebra, F.C.M. Driessens and J.A. Planell, “Setting reaction and hardening of an apatitic calcium phosphate cement”, J. Dent. Res., 76 905-912 (1997).