Bone defects ceramics

The above mentioned scaffolds were made completely of the ceramic materials. Other potential materials which could be used to fabricate a novel construct for the repair of ciitical-sized bone defects is a novel material made of biodegradable polymer reinforced with ceramics particles. The properties of such a composite depend on 1) properties of the polymer used for the matrix and properties of the ceramics used for the reinforcement, 2) composition of the composite (i.e. content of ceramic particles) and 3) size, shape and arrangement of the particles in the matrix. Several polymer-composite composites have been used for scaffolds fabrication including polylactide (PLA) and polycaprolacton (PCL) reinforced with calcium phosphate (CaP) micro and nanoparticles. Authors proposed a novel composite material by blending copolymer -Poly(L-lactide-co-D,E-lactide) (PLDLLA) a copolymer with a ceramic - Tri-Calcium Phosphate... 

There is a high potential for using bioceramics in bone tissue replacement and regeneration. The study shows possibility of treatment of bone defects using the porous alumina grafts, calcite porous scaffolds, polymer/ceramic biocomposite scaffolds, and ceramic coatings. 

Ricci J.L., Bajpai P.K., Berkman A., Alexander H., and Parsons J.R. 1986. Development of a fast-setting ceramic based grout material for filling bone defects. In Biomedical Engineering V Recent Developments. Proceedings of the Fifth Southern Biomedical Engineering Conference. Shreveport L.A. and S. Saha (Eds.), pp. 475-481. Pergamon Press, New York. 

A few million patients every year need a bone graft or bone graft substitute to repair a bone defect resulting from an injury or a disease. A large number of bone graft substitutes can be used unprocessed or processed allogenic bone, animal-derived bone substitutes and synthetic bone substitutes, mostly ceramics. ... 

Another important trend in the future will be the improvement in the biological properties of bone substitutes, the aim being to transform a bone defect into new mature bone as fast as possible. This implies that the focus will be set on resorbable materials that possess an open-porous structure allowing cells to invade the structure. Another potential focus could be set on osteoinductive ceramics. A number of authors have indeed observed that ceramic bone graft substitutes implanted under the skin or in muscles are filled or coated with bone over time. However, despite very intensive research, there is only a poor understanding of the mechanisms leading to osteoinduction, and as a result, it is not possible at the moment to design an osteoinductive ceramic. 

Hydroxyapatite (HA) nanoparticles are osteoconductive bioactive ceramics that can support bone cell adhesion and proliferation and accelerate bone defects healing. HA is typically added to polymeric nanofibers to increase their mechanical strength. HA, often in the form of needle-like nanoparticles, was electrospun in the presence of synthetic biocompatible and biodegradable polymers such as PLA [5, 58-60] and PLA-PEG-PLA [61], natural polymers such as chitosan [62] and collagen [63, 64], and blends of natural and synthetic polymers such as PVA/chitosan [65] and PCL/gelatin [66]. 

Various types of novel materials based on inorganic substances have been developed for biomedical applications over the last three decades. Some of them already play an important, and indispensable role in repairing bone defects, and in cancer treatments. New, advanced ceramic-based materials are expected to be developed for minimally invasive medical treatments in the future. 

Hydroxyapatite ceramics have been successfully used in dentistry, facial surgery, orthopaedics and otolaryngology in the form of shaped pieces and porous granules for replenishment of bone defects in the locations which do not bear mechanical load (e.g. malleus). Wider use of this ceramics, despite their best bioactivity and biocompatibility, is limited due to their poor mechanical properties. 

Due to its good properties of biocompatibility, bioactivity and mechanical properties glass-ceramics A/W is used from the Eighties, for the reconstructions of the iliac crests, artificial vertebrae, intervertebral discs. Glass-ceramics A/W can easily machined into various shapes using discs and reels of diamond, even into screws and in powder form can be used to repair and fill bone defects. 

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