Bone-substituting materials

Ohtsuki, C., Miyazaki, T. and Tanihara, M. (2002) Development of bioactive organic-inorganic hybrid for bone substitutes. Materials Science and Engineering C, 22, 27-34. 

Calcium PolyP fibre has been synthesized (Griffith, 1992) and new high-performance calcium polyphosphate bioceramics has been proposed as a bone-substitute material (Nelson et al, 1993 Pilliar et al, 2001). The in vivo experiments, in which porous rods of calcium PolyP were implanted in the distal femur of rabbits, show that these rods can support bone ingrowth and give no adverse reaction (Grynpas et al, 2002). 

Ideally, bone substitute materials should be replaced by mature bone without transient loss of mechanical support. Unfortunately, at present there is no material available fulfilling these requirements. Consequently, mechanically unstable bone defects ought to be stabilised with a non-resorbable metallic fixation made from stainless steel or titanium and the bone defect filled with a bone graft substitute. While the mechanical properties of the bone graft substitute are of minor importance, much more important it is to optimise the resorption rate of the bone graft substitute to minimise the time required for bone healing (Bohner, 2010). To control the resorption rate several strategies such as modification of the... 

Sarkar MR, Wachter N, Patka P, Kinzl L (2001) First histological observations on the incorporation of a novel calcium phosphate bone substitute material in human cancellous bone. J Biomed Mater Res 58 329-334... 

J. A. Jansen, Development of bone substitute materials from biocompatible to instructive , J. Mater. Chem. 20 (40) (2010) 8747-8759. 

A. Yokoyama, S. Yamamoto, T. Kawasaki, T. Kdigo, M. Nakasu, Development of calcium [4ios[hate cement using chitosan and citric acid for bone substitute materials, Biomataials 23 (2002) 1091—1101. 

S. Roy, S. Pal, Characterization of silane coated hollow sphere alumina-reinforced ultra high molecular weight polyethylene composite as a possible bone substitute material. Bull. Mater. Sci. 25, 609-612 (2002)... 

Low KL, Tan SH, Zein SH, Roether JA, Mourino V, Boccaccini AR. Calcium phosphate-based composites as injectable bone substitute materials a review. J Biomed Mater Res B Appl Biomater 2010 94B(1), 273-286. 

Ignatius, A.A., Wolf, S., Augat, P. and Claes, L.E. (2001) Composites made ofrapidly resorbable ceramics and poly(lactide) show adequate mechanical properties for use as bone substitute materials. Journal of Biomedical Materials Research, 57, 126-131. 

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). 

Bone substitute materials patented in the US. http //www.zgnmjs.com/news/10703736. html 2011 [accessed 29.06.14]. 

Schneider OD, Weber F, Brunner TJ, Loher S, Ehrbar M, Schmidlin PR, et al. In vivo and in vitro evaluation of flexible, cottonwool-Uke nanocomposites as bone substitute material for complex defects. Acta Biomater 2009 5 1775-84. 

Hydroxyapatite is currently much in demand as a constituent of bone cements and bone substitute materials (Chapter 12.14). 

Injectable bone substitute material consisting of CTS, citric acid, and glucose solution as the liquid phase, and tricalcium phosphate powder as the solid phase, was developed by Liu and coworkers [141]. Four types of cements have been used to investigate the mechanical properties and in vitro biocompatibility of the material. In the presence of citric acid, tricalcium phosphate partially transformed into HAp and dicalcium phosphate. 

Zhang L, Li Y, Yang A (2005) Preparation and in vitro investigation of chitosan/nanohydrox-yapatite composite used as bone substitute materials. J Mater Sci Mater Med 16 213-219... 

Liu H, Li H, Cheng W (2006) Novel injectable calcium phosphate/chitosan composites for bone substitute materials. Acta Biomater 2 557-565... 

Recently, a joint project between material scientists, cell biologists, and clinicians was installed aiming at local and time-controlled dehvery of osteoporotic drags from implant or bone-substituting materials. Before drag-loaded PEC particles were studied. 

Calcium orthophosphates are chemical compounds of sp>ecial interest in many interdisciplinary fields of science, including geology, chemistry, biology and medicine. The main driving force behind the use of calcium orthophosphates as bone substitute materials is their chemical similarity to the mineral component of mammalian bones and teeth... 

Based on observed tissue response, synthetic bone-graft substitutes can be classified into inert (e.g., alumina, zirconia), bioactive (e.g., hydroxyapatite, bioactive glass), and resorbable substitutes (e.g., tricalcium phosphate, calcium sulfate). Of these, resorbable bone-graft substitutes are preferred for bone defect filling because they can be replaced by new natural bone after implantation, p-tricalcium phosphate (Ca3(PO )2, p-TCP) is one of the most widely used bone substitute material, due to its faster dissolution characteristics. Preparation of magnesium-substituted tricalcium phosphate ((Ca, Mg)3(PO )2, p-TCMP) has been reported by precipitation or hydrolysis method in solution. These results indicate that the presence of Mg stabilizes the p-TCP structure (LeGeros et al., 2004). The incorporation of Mg also increases the transition temperature from p-TCP to a-TCP and decreases the solubility of p-TCP (Elliott, 1994 Ando, 1958). 

Bone is a living tissue and undergoes a constant change in composition by either dissolving or deposition of bone minerals through osteoclast and osteobalst cells, respectively. The nano-HA has a nano-crystaUine feature similar to the bone, thus being sued as the bone substitute material [1-3]. 

Tadic, D. and Epple, M. 2004. A thorough physicochemical characterisation of 14 calcium phosphate-based bone substitution materials in comparison to natmal bone. Biomaterials, 25,987-994. 

Piticescu, R. M., L. M. Popescu, and T. Bimiiana. 2012. Composites containing hydroxyapatite and polyurethane ionomers as bone substitution materials. Dig. J. Nanomater. Biostruct. 7 477 85. 

Wu, X., X. Liu, J. Wei, J. Ma, F. Deng, and S. Wei. 2012. Nano-Ti02/PEEK bioactive composite as a bone substitute material In vitro and in vivo studies. International Journal of Nanomedicine 7 (January) 1215-1225. doi 10.2147/IJN.S28101. http //www.pubmedcentral.nih.gov/ arliclerender.fcgi artid = 3298387 tool = pmcentrez rendertype = abstract. 

S. Meyer, T. Floerkemeier and H. Windhagen, Histological osseointegration of a calcium phosphate bone substitute material in patients. Biomed. Mater. Eng. 17 347-356,2007. 

Moreover, a rarmber of different prosthetic devices based on PLA have been developed in orthopedic fixation or as bone substitution materials. The choice of this PLA polymer is... 

Strietzel et al. [14] conducted a preliminary two-center cUnical prospective study to evaluate the tissue composition of augmented sites with a nanocrystaUine HA (ncHA) bone substitution material using cUnical and histological examinations. 

Strietzel, F.P., Reichart, P.A., Graf, H.L (2007) Lateral alveolar ridge augmentation using a synthetic nano-crystalline hydroxyapatite bone substitution material (Ostim ). Preliminary clinical and histological results. Clinical Oral Implants Research,... 

Rueger, J.M. (1998) Bone substitution materials. Current stams and prospeds. Orthopade, 27, 72-9. 

Silica-based BGs are a group of surface-reactive glass-ceramic (GC) biomaterials, first prepared by Hench et al. in 1969 [38]. BGs possess excellent biocompatibility, the ability to bond with bone and other tissues and stimulatory effects on bone ceU function [39 1] which explain their successful application as bone-substitute material for non-load-bearing applications in orthopaedic and dental surgery [41,42],... 

Schneider, O. D., et al., / vivo and in vitro Evaluation of Flexible, Cotton wool-like Nanocomposites as Bone Substitute Material for Complex Defects. Acta Biomateria-lia, 2009, 5(5), 1775-1784. 

Several synthetic materials for bone substitution have been developed and characterized during the last few decades. Different approaches have been used for the design of bone substitute materials. Most are formulated as granules of different sizes or porous blocks (or sponges). The aim of this section is to provide an overview of the currently available ceramic bone substitutes. 

The limitations previously described suggest the need for various handling requirements to promote a reliable and safe clinical application. In fact, easy handling is of paramount importance for the commercial success of bone substitute materials. Thus, the current challenge to potentiate the clinical application of the ceramic-based SBS lies on the development of injectable bone substitutes (IBSs), in which a binder or gel is added to the granules. 

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