Alteration of Acrylic Bone Cement by Chemicals Used during Hard Tissue Specimen Processing

Abstract

Accurate characterization of the bone-cement-implant interface often requires hard tissue techniques to prepare retrieved implants for analysis. However, chemicals used for specimen processing can alter and degrade the cement interface. With few exceptions, cement degradation caused by specimen processing has not been systematically and quantitatively assessed. This is especially the case for the new non-formalin based fixatives currently being marketed. We measured physical and mechanical changes that accumulated over time as bone cement was exposed to different chemicals routinely used for fixation, dehydration, and embedding hard tissue specimens.

Cylindrical bone cement plugs were submersed into 14 different chemical solutions according to applicable histological protocols. After exposure to the chemicals, the weight, volume, and compressive strength of each specimen was measured. The type of chemicals used for fixation, dehydration, and infiltration, and the length of time in solution were significant factors in the physical and mechanical differences observed. Consideration of these factors will enable choice of appropriate fixatives, dehydrators, and embedding media to allow maintenance of the bone-cementimplant interface-without processing artifacts or mechanical aberrations and will insure accurate interpretation of cement mantle characteristics observed. (The J Histotechnol 21:107, 1998)

Keywords:

• biomaterials
• bone cement
• hard tissues
• nonformalin based fixatives
• orthopedic implant
• plastic embedding