Implants hard tissue response

Bioadhesion, i.e. biofihn formation resulting in a fouling surface, is required for biomaterial to be considered as a part of the body (e.g., orthopedic prosthesis, hard tissue) to enhance its incorporation and its biomechanical response. Examples are in the rebuilding of bones, recolonization, and hybrid implants composed of two parts, a synthetic one (with polymers as the mechanical sub-... 

Stress Shielding. Beyond the traditional biocompatibility issues, hard tissue biomaterials must also be designed to minimize a phenomenon known as stress shielding. Due to the response of bone remodeling to the loading environment, as described by Wolffs law, it is important to maintain the stress levels in bone as close to the preimplant state as possible. When an implant is in parallel with bone, such as in a bone plate or a hip stem, the engineered material takes a portion of the load— which then reduces the load, and as a result, the stress, in the remaining bone. When the implant and bone are sufficiently well bonded, it can be assumed that the materials deform to the same extent and therefore experience the same strain. In this isostrain condition, the stress in one of the components of a two-phase composite can be calculated from the equation ... 

Furthermore, these scaffolds have been shown to be both biodegradable and biocompatible in vivo. Results indicated that PPF is biocompatible within both soft and hard tissues, minimal fibrous encapsulation of the scaffolds occurred, and tissue response appeared to improve with implantation time. A progressive reduction in inflammatory cell density and a continued organization of connective tissue with the interstitial space was observed, even if scaffold microstmcture did not seem to play a key role. ... 

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