Volume variations of bone tissue after undergoing different physical and chemical treatments

Both autogenic and allogenic bone has been employed through different surgical procedures to fill different defects or as osteosynthesis materials. Some physical and/or chemical treatments are usually necessary before its use. Since bone volume is important from a surgical point of view, the present study was designed to analyse its possible variations when subjected to certain procedures. Screws made of bovine cortical bone were autoclaved in different conditions regarding time and vacuum (A1-A2), cryopreserved, demineralised, enzymatically digested and rehydrated. The samples were measured before and after every treatment. Sterilisation caused a volume reduction more marked with method A1 than A2 whereas freezing allowed to obtain the original size. No volumetric changes were registered after demineralisation and enzymatic digestion. Rehydration significantly increased their volume already during the first hour but the maximum value was reached at 24 h. Thus, autoclaving was the only treatment able to reduce the bone volume whilst freezing and rehydration allowed the samples to return to their original size.