Background: Bone graft studies lack standardized controls. We aim to present a quick and reliable method for the intra-operative generation of acellular bone explants.
Methods: Therefore, ovine cancellous bone explants from the iliac crest were prepared and used to test several methods for the induction of cell death. Over night heat inactivation was used as positive treatment control, methods to be investigated included UV light, or X- ray exposure, incubation in a hypotonic solution (salt-free water) and a short cycle of repeated freezing and thawing.
Results: Viability of treated and 2 days cultured bone explants was investigated by lactate dehydrogenase assay. Non-treated cultured control explants maintained around 50% osteocyte viability, while osteocyte survival after the positive treatment control was abolished. The most dramatic loss in cell viability, together with a low standard deviation, was a repeated cycle of freezing and thawing.
Conclusions: To summarize, we present a freeze-thaw method for the creation of acellular bone explants, which is easy to perform, not time-consuming and provides consistent results.