A Review on Importance and Recent Applications of Polymer Composites in Orthopaedics

The idea of using composite in bone implant came since 1980 . Considering the observed problems and failures from the previous materials, using composite materials with higher strength and stiffness and more similarity to natural bone had started to develop. In medical composites at least one of the constituent materials should be bioactive (metal-polymer or ceramic). The name of composites is based on their matrix phase (metal-ceramic or polymer). In manufacturing of medical composites, bioactivity is a main factor that should be considered in choosing the material. Bones as a hard tissue are strong and stiff and clearly have high elastic modules. Human Bones are naturally and structurally composite material made of collagen fibers and Nano crystals of hydroxyapatite which are sediment in collagen fibers.The collagen fibers have low elastic modulus and hydroxyapatite is with high elastic modulus and contain almost 70% of bone dry weight and supports the stiffness of the bone. Regarding this fact, composite material could represent great biocompatibility. Nowadays it is proved that composite materials are a very good choice and substitute for bone implant in orthopedic surgeries.