Performance of bone cements: Are current preclinical specifications adequate?

• Published in: Acta orthopaedica 2008-01, Vol.79 (6), p.826-831
• Main Authors: Nottrott, Markus, Mølster, Anders O, Moldestad, Irene O, Walsh, William R, Gjerdet, Nils R
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; Bone Cements - standards; Compressive Strength; Diseases of the osteoarticular system; Humans; Materials Testing - standards; Medical sciences; Stress, Mechanical; Traumas. Diseases due to physical agents
• ISSN: 1745-3674; 1745-3682
• DOI: 10.1080/17453670810016920

Background Current specifications (standards) for preclinical testing of bone cements (ISO 5833: 2002, ASTM F451-99a) require simple mechanical testing after ageing for 24 h under dry conditions at 23°C. Some bone cements have fulfilled the requirements in the specifications, and yet had inferior clinical results. Clinically, bone cements are subjected to complex loading patterns in a moist or wet environment at 37°C. Thus, both the validity and the robustness of current standard testing protocols can be questioned. Methods We examined the influence of temperature and storage medium on the properties of bone cement. We also compared the results of storage and testing under standard conditions of 23°C in dry air, with the results obtained at 37°C in water or plasma. Results The dry specimens showed an increase in strength and elastic modulus with time, while the values of the wet ones decreased. There was no difference between specimens stored in water or in plasma. Ultimate compressive strength of dry specimens after 24 h was 1.16 times higher than that of the ones stored wet, increasing to 1.34 times after 1 month, and 1.46 times after 6 months (p