Bone-bonding material

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... 

Bioactive ceramics have already played an important role in bone repair in the clinical fields because of their ability to bond to living bone. However, the use of these bioactive ceramics is limited because of their brittleness and higher Young s modulus than bone. The combination of ceramic and organic components provides us with a design for novel tissue-repairing materials. The establishment of these techniques promises a novel bone repairing material. 

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 ... 

As bone substitution materials, calcium orthophosphates are researched for more than 80 years. The most significant characteristics of calcium phosphates are their bioresorbtion and bioactivity. They are non-toxic and biocompatible. Bioactivity shows as an ability to create a physical chemical bond between an implant and a bone. This process is called ostheointegration (Dorozhkin, 2009b). 

Ito, M., Hidaka, Y. 1997. A chitosan bonded hydroxyapatite bone filling material. In Chitin Handbook, ed. RAA. Muzzarelli, pp. 373-389. Grottammare, Italy Atec. 

Bioceramics have now been widely used as bone replacement materials in orthopaedic surgery. In particular, calcium phosphate ceramics have been applied as bioactive ceramics with bone bonding capacities. 

Biological responses such as bone bonding and the biodegradation properties of these materials are very important in clinical applications. Any convincing conclusion has not yet been reached as to whether these materials are biodegradable or not, although it has been discussed for a long time. 

In an in vivo study that lasted 5-7 years, Hasegawa et al. [16] investigated the biocompatibility and biodegradation of HA/PLLA composite bone rods using non-calcined HA (n-HA) and calcined HA (c-HA) that were implanted into the distal femurs of 25 rabbits. The n-H A/PLLA composites showed excellent biodegradabUity and osteoconductivity. Newly formed bone surrounded the residual material and trabecular bone, bonded to the rod, was observed toward the center of the implant. 

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