Process for demineralization of bone matrix with preservation of natural growth factors

A method for producing a three dimensional matrix, comprising:

• seeding a demineralized bone matrix with cells to form the three dimensional matrix, wherein the demineralized bone matrix was produced by a method comprising:
• placing a bone body in a first processing solution comprising an acid to demineralize the bone body, wherein the demineralized bone body comprises bone fragments with at least one dimension greater than 2 mm;
• periodically removing the bone body from the first processing solution to perform at least one test on a mechanical property of the bone body;
• and
• exposing the bone body to a second processing solution when the test yields a desired result to produce a demineralized bone matrix, wherein the demineralized bone matrix comprises less than 2% residual calcium, wherein the test comprises a compression test on the bone body, wherein the compression test comprises applying a compressive force in a range from about 10 g-force/cm2 to about 4000 g-force/cm2 until the bone body uniformly compresses to less than about 60 percent of its original shape;
• or wherein the test comprises a bending test, wherein the bending test comprises applying a bending force in a range from about 10 g-force/cm2 to about 4000 g-force/cm2.