Bone bonding

However, more recent work about using the PEG/PBT as a bone substimte in critical size defects in the iliac bone of goats and humans did not show the expected good bone-bonding and calcification behaviors. Reasons for the discrepancy with the earlier results in small animals may be caused by the differences in regenerative capacity between the species, the size of the defect, and the type of bone into which the substitute was implanted. 

Sakkers RJB, Dalmeyer RAJ, Wijn JR, and Blitterswijk CA. Use of bone-bonding hydrogel copolymers in bone An in vitro and in vivo study of expanding PEO-PBT copolymers in goat femora. J Biomed Mater Res, 2000, 49, 312-318. 

Reed AM and Gilding DK. Biodegradable polymers for use in surgery-poly(ethylene oxide) poly (ethylene terephthalate) (PEO/PET)copolymers 2. in vitro degradation [J]. Polymer, 1981, 22,499-504. Van Blitterswijk CA, Brink JVD, Eeenders H, et al. The effect of PEG ratio on degradation, calcification and bone bonding of PEO/PBT copolymer (Polyactive). Cell Mater, 1993, 3(1), 23-36. 

Radder AM, Leenders H, and van Blitterswijk CA. Bone-bonding behaviour of PEO/PBT copolymer coatings and bulk implants A comparative study. Biomaterials, 1994, 21, 532-537. 

The bonding mechanism between glass and bone has been described in detail [ 36]. The basis for bone bonding is the reaction of the glass with the surrounding solution. A sequence of interfacial reactions, which begin immediately after the bioactive material is implanted, leads to the formation of a CHA layer and the establishment of an interfacial bonding. The sequence of interfacial reactions can be summarized as follows ... 

Fibro-vascular tissues require a pore size greater than 500 pm for rapid vascularisation, whereas the optimal porosity for bone-bonding materials is considered to be between 70 and 200 pm. Textile structures have the potential to be tailored in such a way as to provide the required porosity in terms of size, quantity and distribution pattern. For example, in a typical textile... 

Figure 1. Tensile strength of cyanoacrylate—bone bond after storage in water...

As emphasised by Gross (1994), bioactive ceramic surfaces, in particular hydroxyapatite with positive effects favour bone bonding by... 

Kobayashi, T., Itoh, S., Nakamura, S., Nakamura, M., Shinomiya, K., and Yamashita, K. (2007) Enhanced bone bonding of hydroxyapatite-coated titanium implants by electrical polarization. J. Biomed. Mater. Res. A, 82, 145-151. 

Porter, A.E., Taak, P., Hobbs, L.W., Coathup, M.J., Blunn, G.W., and Spector, M. (2004) Bone bonding to hydroxyapatite and titanium surfaces on femoral stems retrieved from human subjects at autopsy. Biomaterials, 25 (21), 5199-5208. 

Joris SJ, Amberg CH (1971) The natnre of deficiency in nonstoichiometric hydroxyapatite. 11. Spectroscopic stndies of calcium and strontium hydroxyapatite. J Phys Chem 75 3172-3178 Kato H, Nishiguchi S, Furukawa T, Neo M, Kawanabe K, Saito K, Nakamura T (2001) Bone bonding in sintered hydroxyapatite combined with a new synthesized agent, TAK-778. J Biomed Mater Res 54 619-629... 

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