The Cell–Surface Interaction - Tissue Engineering: Cell-Surface Interactions for Tissue Culture - page 17

Pull Out test for TAN Intramedullary Nails

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TAN S TAN Pol

Fig. 4 Atomic force and scanning electron microscopy images of the polished TAN surface
show how this technique is successful at reducing the characteristic surface roughness of the
material. This modification produces a fibro-osseous interface (white arrows) which significantly
impacts the ease with which the implants can be removed (*p = 0.05)

implantation completely mask such fine topographies and, therefore, their effective
cue to relevant cells is masked or becomes insignificant. Numerous studies have
shown major changes in cell behaviour above the 2-lm discontinuity size, but
Richards postulated that the effect appears to become more and more marginal
upon cells as the size increases. Despite this, most studies still include samples
with average roughness of approximately 5 lm and designate their 'smooth'
surface to be less than 0.6 lm[ 67 , 84 ]. Clearly, this requires a degree of stan-
dardization for studies to be comparable. So theoretically, there is a consensus that
a roughness spectrum exists; however, there is clear overlap and outright dis-
agreement regarding the boundaries of the effective limits of the spectrum.
Although these issues can make discerning valuable information regarding
interesting surface properties and cellular reactions difficult, the issue is further
clouded

with the introduction of nanotopography. Several groups have