Bioceramic coatings compositions

In this chapter common methods to evaluate chemical properties and phase composition of bioceramic coatings will be briefly described that are available in many laboratories including X-ray diffraction (XRD), vibrational spectroscopy techniques such as infrared (FTIR) and Raman spectroscopy and nuclear magnetic resonance spectroscopy (NMR). These methods provide a host of information on bulk phase composition, degree of crystallinity and crystallite size. Some special techniques including cathodoluminescence serve to reveal intrinsic coating properties that cannot be assessed by conventional analytical techniques, for example to distinguish between amorphous calcium phosphate (ACP) and crystalline calcium phosphates. 

There are multiple applications of fluoridated bioceramics, essentially as bone and tooth substitutes (Table 1), involving bulk ceramics, glasses, composite materials and coatings for medical devices and surface treatments. In some cases, fluoride ions can leach out of the material inducing a direct biological effect in a soluble form. However, considering the affinity of fluoride ions for apatite... 

Structure of calcium titanate/titania bioceramic composite coatings on titanium alloy and apatite deposition on their surfaces in a simulated body fluid. Surf. Coat. Technol., 201, 8715-8722. 

Karthikeyan, J. (2009) Bioceramic composite coatings by cold spray, in Thermal Spray 2009 Expanding Thermal Spray Performance to New Markets and Applications, ASM International, pp. 391 -396. 

Radin SR, Ducheyne P (1992) Plasma-spraying induced changes of calcium phosphate ceramic characteristics and the effect on in vitro stability. J Mater Sci Mater in Med 3 33-42 Ramires PA, Romito A, Cosentino F, Milella E (2001) The influence of titania/hydroxylapatite composite coatings on in vitro osteoblasts behaviour. Biomaterials 22 1467-1474 Ravaglioli A, Krajewski A (1992) Bioceramics Materials, Properties, Applications. Chapman and Hall, London... 

If a nearly inert material is implanted into the body it initiates a protective response that leads to encapsulation by a nonadherent fibrous coating about 1 i.m thick. Over time this leads to complete isolation of the implant. A similar response occurs when metals and polymers are implanted. In the case of bioactive ceramics a bond forms across the implant-tissue interface that mimics the bodies natural repair process. Bioactive ceramics such as HA can be used in bulk form or as part of a composite or as a coating. Resorbable bioceramics, such as tricalcium phosphate (TCP), actually dissolve in the body and are replaced by the surrounding tissue. It is an important requirement, of course, that the... 

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