Implant Surface Properties

Principles In this process, ions of almost any material can be implanted into a substrate to alter its surface properties, such as resistance to wear, corrosion, and oxidation, as well as many others. The implanted material is not... 

Properties of the deposit The changes in surface properties of implanted materials which can be achieved are very considerable. Physical and chemical properties can be widely varied to produce special characteristics, some of which cannot be obtained in any other way. 

R. E. Baier, Surface Properties of Materials for Prosthetic Implants, Calspan Corporation, CAL Report VH-2801-p-2 (February 1970). 

The increasing demand for synthetic biomaterials, especially polymers, is mainly due to their availability in a wide variety of chemical compositions and physical properties, their ease of fabrication into complex shapes and structures, and their easily tailored surface chemistries. Although the physical and mechanical performance of most synthetic biomaterials can meet or even exceed that of natural tissue (see Table 5.15), they are often rejected by a number of adverse effects, including the promotion of thrombosis, inflammation, and infection. As described in Section 5.5, biocompatibility is believed to be strongly influenced, if not dictated, by a layer of host proteins and cells spontaneously adsorbed to the surfaces upon their implantation. Thus, surface properties of biomaterials, such as chemistry, wettability, domain structure, and morphology, play an important role in the success of their applications. 

In addition, the ability to optimize biosensor design is of central importance and initially depends on the determination of what aspects of the foreign body reaction and biosensor surface properties are critical to the success of the implanted biosensor. To accomplish this efficiently, it would be very beneficial if active sensors could be imaged in situ. Thus, sensor performance could be quantified relative to the manipulation of local tissue and microvascular conditions in response to various implant properties. Some important implant features include surface texture, porosity, and surface material composition. Surface texture of the implant has been observed to affect the extent of collagen formation. Smooth implant surfaces, which the local... 

A. Surface Properties of Nanophase Ceramics for Enhanced Orthopedic and Dental Implant Efficacy... 

In spite of these investigations, many reports in the literature demonstrate that these nanoapatite ceramics are not always osteoinductive and, furthermore, do not possess mechanical properties similar enough to bone for sustained osseointegration (Muller-Mai el al., 1995 Doremus, 1992 Du et al., 1999 Weng et al., 1997), criteria necessary for increased orthopedic and dental implant efficacy. Moreover, mechanisms of osteoinduction of calcium phosphate ceramics are not clear and seem to depend on specific nanoapatite material properties (such as surface properties and crystallinity) and the animal tested (i.e., dog versus rabbit). Undoubtedly, the incidental cases of calcium phosphate biomaterial-induced osteogenesis indicate promise in... 

Due to their ability to selectively promote both osteoblast and osteoclast function, nanophase ceramics provide a preferable alternative to conventional orthopedic and dental implants that fail to integrate with surrounding bone it is undoubtedly highly desirable to minimize, if not avoid, clinical complications that necessitate removal of failed implants as a result of poor surface properties that lead to insufficient osseointegration. These results provide evidence that nanoceramics may be synthesized to match surface properties of bone and, thus, demonstrate strong promise and potential for their use in orthopedic and dental applications. 

Ashworth, V. Grant, W.A. Procter R.P.M., Eds. Proc. Int. Conf. Modification of Surface Properties. Ion Implantation Oxford Press, New York, 1987. 

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