Artificial Bone Made of Wood

A new procedure to turn blocks of wood into artificial bones has been developed by Italian scientists (in Instituto Di Scienza E Techologia Dei Materiali Ceramici), who plan to implant them into large animals, and eventually humans.

They say the wood-derived bone substitute should allow live bones to heal faster and more securely after a break than currently available implants.Wood closely resembles the physical structure of natural bone, which is very difficult to reproduce with conventional processing technology.

To create the bone substitute, a block of wood, red oak, is heated until all that remains is pure carbon, which is basically charcoal. Then, they should spray calcium over the carbon, creating calcium carbide. Additional chemical and physical steps convert the calcium carbide into carbonated hydroxyapatite, which can then be implanted and serves as the artificial bone.

hardwood microstructure

cancellous bone microstructure

Gecko setae

Gecko setae stick more strongly the faster they slide. This is because friction between dry, hard, macroscopic materials typically decreases at the onset of sliding, and as velocity increases, friction continues to decrease because of a reduction in the number of interfacial contacts, due in part to wear. Gecko setae did not exhibit the decrease in adhesion or friction characteristic of a transition from static to kinetic contact mechanics. Instead, friction and adhesion forces increased at the onset of sliding and continued to increase with shear speed from 500 nm/s to 158 mm/s.

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(Rate-dependent frictional adhesion in natural and synthetic gecko setae, by Gravish et al)