The present invention is a specialized implant having opposed surfaces for
engaging each of the vertebral bodies adjacent a disc space into which
the implant is implanted. The surface comprises arrayed projections
having at least one forward facing facet directed at least in part toward
the leading end of the implant and at least one rearward portion directed
at least in part toward the opposite trailing end of the implant. Each of
the forward facet and rearward portion has a length and a slope. The
length of the forward facet is longer than the length of the rearward
facet. The slope of the rearward facet is steeper than the slope of the
forward facet. The surface projections also have opposed side facets
directed generally toward the sides of the implant. The side facets are
located between the forward facet and rearward facet and converge toward
each other in a direction away from the base of the surface projections.
The surface may also include projections having left and right forward
side facets and a rearward facet. The surface further may include
projections having left and right rearward side facets and a forward
facet.