Strategy for a Biomimetic Paradigm in Dental and Craniofacial Tissue Engineering - Biomimetics: Advancing Nanobiomaterials and Tissue Engineering - page 139

calcifi ed matrix on the implant surface is followed by the arrangement
of the woven bone and bone trabeculae. This suggested that the implant
surface is positively recognizable from the osteogenic cells as a biomimetic
scaffold which may favor early peri-implant osteogenesis [129-135].

6.6.2 Implant Surface Modifi cation: Laser Micromachining and

Biomimetic Coating

The surface of an implantable material may be modifi ed so that the biol-
ogy of the surface is better served to interact with the surrounding envi-
ronment (Figure 6.10). This is generally done by laser micro-machining
and micro-texturing and the feature size is on the order of a cell diam-
eter (10μm). Cells interact with grooves or micro-textured patterns at
the micron-scale (Figure 6.11). At the sub-micron scale, the interactions
between cell constituents and the underlying substructure result in bio-
chemical adhesion, while at the nanoscale, the biochemical interactions
between protein molecules and synthetic surfaces promote the self orga-
nization of protein molecules and cell attachment [136]. Indeed, in vitro
experimental studies [137, 138] have demonstrated that well-developed
fi lopodia directly entered nanometer-sized pores for the initial attachment
of osteoblastic cells.
Biomimetic coatings created by the precipitation of calcium phosphate
apatite crystals onto the titanium surface from simulated body fl uids
(SBF) have been shown to be more soluble in physiological fl uids and

Control Laser grooved Laser/RGD

Figure 6.10 SEM of titanium surface.

( a ) ( b ) ( c )

Bone marrow mesenchymal stem cell culture, 1 day

Figure 6.11 Surface laser microgrooves as instructive topography affecting
cellular orientation. (a) Flat surface encourages random cell orientations. (b,c)
Micro-grooves help align the cells through a process called contact guidance .