Apparatus for demineralizing osteoinductive bone

Abstract

The invention is directed to an apparatus for producing demineralized osteoinductive bone. The apparatus demineralizes bone by subjecting bone, including, for example, ground bone, bone cubes, chips, strips, or essentially intact bone, to either a rapid high volume pulsatile acidification wave process or to a rapid continuous acid demineralization process. The pulsatile acidification wave process includes subjecting bone to two or more rapid pulse / drain cycles in which one or more demineralizing acids is rapidly pulsed into a vessel containing bone, and after a desired period of time, is rapidly drained from the vessel. The continuous acid demineralization process includes subjecting bone to a continuous exchange of demineralizing acid solution in which the demineralizing acid solution is recirculated from the container holding the bone through an ion exchange media. Calcium and phosphate are thereby removed from the bone to produce a regenerated acid, and the regenerated acid is returned to the container holding the bone. Both processes allow bone to be rapidly demineralized to a precise and specific desired residual calcium level without sacrificing osteoinductivity.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS [0001] This application is a continuation-in-part of application Ser. No. 10 / 180,989, filed Jun. 26, 2002, which is a continuation-in-part of application Ser. No. 09 / 655,711, filed Sep. 5, 2002, which issued as U.S. Pat. No. 6,534,095 on Mar. 18, 2003, and which claims the benefit of provisional application No. 60 / 152,272, filed Sep. 3, 1999, both of which are herein incorporated by reference.FIELD OF THE INVENTION [0002] The present invention relates to the preparation of bone grafts. The present invention further relates to the demineralization of osteoinductive bone. BACKGROUND OF THE INVENTION [0003] Demineralized freeze-dried bone allograft is widely used in the repair of skeletal defects and periodontal disease. It is known that the implantation of acid demineralized bone in the form of a powder in extraskeletal sites may stimulate new bone formation. Various groups including Syftestad, 1982; Urist et al., 1967; Urist and Strates, 1979; ...

AI Technical Summary

Benefits of technology

[0005] The present invention is directed to an apparatus for producing demineralized osteoinductive bone. The apparatus achieves demineralization of bone by subjecting bone to either a rapid high volume, pulsatile acidification wave process or to a rapid continuous exchange of acid.

Problems solved by technology

These known methods are problematic in that they require prohibitively long periods of time for processing resulting in a very low demineralization rate, require excessive handling of the ground bone being processed, are capable of processing only small amounts of ground bone, and result in a demineralized bone product which exhibits inferior osteoinductivity caused by excessive exposure of bone-inducing proteins in the bone to harsh acids over extended periods of time.

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