Influence of the technique used to crush a bone block graft on the physicochemical properties of particulate bone: an in vitro study using a bovine rib model

Objective: To evaluate the influence of the technique used to crush a bone block on the physical and chemical properties. Materials: and methods: 120 bone blocks were obtained from 30 bovine ribs. Block 1 was used exclusively to analyse bone mineral composition (BMC) (% Ca and P); while blocks 2, 3 and 4 were used to determine volume (V), bone mineral density (BMD), fractal dimension (FD), particle size and BMC, after grinding (block 2), crushing (block 3), and scraping (block 4) the bone. The change in physical properties after crushing the blocks was studied by radiological analysis using microcomputed tomography, while changes in chemical properties were analysed using a field emission scanning electron microscope (FESEM) and a microanalytical system based on energy-dispersive and X-ray spectrometry. Bone particle size was calculated from the FESEM images using an image analysis software. Results: The order of greatest to least increase in V was: scraper>mill>crusher; the order from the least to the greatest decrease in BMD, FD, Ca and P was: scraper<millmill>crusher. Conclusions: : Crushing a bone block with a mill, crusher or scraper produces a much greater increase in V and decrease in BMD, FD, and of Ca and P levels which is more marked with a crusher. Clinical relevance: The use of a scraper or mill to crush bone affects the physical and chemical properties of bone less than when a crusher is used, although further clinical studies are necessary.