Advances in Porous Biomaterials for Dental and Orthopaedic Applications

Materials (Impact Factor: 2.65). 05/2010; 3(5). DOI: 10.3390/ma3052947
Source: DOAJ


The connective hard tissues bone and teeth are highly porous on a micrometer scale, but show high values of compression strength at a relatively low weight. The fabrication of porous materials has been actively researched and different processes have been developed that vary in preparation complexity and also in the type of porous material that they produce. Methodologies are available for determination of pore properties. The purpose of the paper is to give an overview of these methods, the role of porosity in natural porous materials and the effect of pore properties on the living tissues. The minimum pore size required to allow the ingrowth of mineralized tissue seems to be in the order of 50 µm: larger pore sizes seem to improve speed and depth of penetration of mineralized tissues into the biomaterial, but on the other hand impair the mechanical properties. The optimal pore size is therefore dependent on the application and the used material.

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Available from: Michael Morlock, Oct 14, 2015
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    • "Basic bone composition consists of mostly fibrous protein collagen, carbonated apatite [Ca5(PO4, CO3)3(OH), CAP], and water.21,22 Some previous studies indicated that bone contains many different structures and is highly porous on the micrometer scale.23–25 A current strategy is to consider natural bone as a nanostructured material.26 "
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    • "The mass (liquid) redistribution in virgin media at constant or variable conditions imposed by the penetrating liquid at the boundary interface is a problem relevant to many technological processes such as bonding of paper [2] , wood [3] , bonding of metals [4] [5], dental medicine [6] [7], bone repairing [8], etc. Commonly during the process the filler liquid is imposed at the boundary x = 0 as a limited amount of substance (a momentary source) in the form of a thin layer with thickness negligible with the respect to the scales of the contacting bodies which have to be bonded. There exist two approaches in modelling the liquid penetration process, namely: (a) Transient diffusion with constant concentration at the boundary x = 0 which is commonly used in modeling the transient liquid phase bonding of metal alloys where a thick layer of a bonding metal (which consequently melts and penetrates) is used [4] [5] [9]. "
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    • "% HAP and (f) with 10 wt. % HAP after sintered at 1200°C as vascularization (Mour et al. 2010). Figure 1 "
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