A New Look at the Blade Implant.

Abstract

T he blade was originally designed due to the need for an implant for knife-edge and extremely shallow ridges, which had presented problems for root-form implants and tripodal pins. Linkow recognized the time had come to move completely from trying to duplicate or simulate the roots of teeth with implant designs. It is the very nature and morphology of natural teeth that, in time, they may have to be extracted because of periodontal conditions. The roots are lost at the expense of the labial and buccal plates of bone, seldom due to loss of the palatal or lingual bone. Nature made a mistake: It provided a maximum amount of bone on the lingual and palatal cortices, where it is not needed, and a minimum amount of bone flanking the teeth labially and buccally, where it is needed to resist lateral forces, anterior thrusts of the tongue, and premature contact of the teeth during lateral and eccentric movements of the mandible. When the teeth are lost, periodontal stimulation to the bone terminates, so it resorbs due to hypofunction. A venous, arterial, and capillary stasis takes place, causing swelling, engorgement, and edema of the blood vessels, thereby creating pressure to the bone beyond its physiologic capacity, causing resorption. How could one expect to reenter the severely resorbed edentulous ridge 5 or 10 years after the teeth were lost with an implant resembling the root of a tooth when most of the depth and width of bone needed for support has been lost? An implant had to be designed that utilizes the horizontal rather than the vertical dimension. It also had to be designed with large openings, or vents, in its body to allow for osteogenesis to occur. It had to be designed in such a way that its wedge-shaped body could be angled obliquely off the horizontal plane, bisecting the severely angled bone that usually exists in the maxillae. It had to be designed to permit bending or adjusting of the necks so that the posts of the implants would be parallel either to one another or to the remaining prepared abutment teeth. A technique for blade insertion had to be designed and simplified so that dentists could do it successfully with minimum difficulty. The endosteal blade implant can resist lateral forces possibly just as good as natural teeth for several reasons: