Mechanical Properties of Calcium Phosphate Cements (CPC) for Bone Substitution: Influence of Fabrication and Microstructure

Abstract:

Calcium phosphate cements have been widely used in medical and dental applications for decades. However, their intrinsic high brittleness and low strength prohibit their use in many stress-bearing locations, which would require an improvement in mechanical properties. The influence of microstructural parameters on the latter have nevertheless barely been investigated in a systematic manner. Furthermore, due to their inferior reproducibility which is sensitive to the variations introduced during the preparation and the way they are measured, mechanical properties of CPC cannot simply be characterized using mean values, but request a more reliable method. In this aim, apatite cements have been fabricated by mixing liquid and powders based on α-TCP (α-tricalcium phosphate), and their mechanical properties have been measured (Young’s modulus, fracture toughness, compressive strength and flexural strength) in wet environment as a function of various parameters (liquid-to-powder ratio; amount and morphology of porosity, including macropores created by porogens). The reliability of compressive strength of CPC is analysed using Weibull statistics. The above results indicate that fabrication and microstructural features of CPC significantly influence their mechanical properties.

• Periodical: Key Engineering Materials (Volumes 493-494)
• Pages: 409-414
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.493-494.409
• Online since: October 2011
• Authors: Jing Tao Zhang, Franck Tancret, Jean Michel Bouler
• Keywords: Bone Substitute, Calcium Phosphate, CaP, Fracture Stress, Reliability, Toughness

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