In some cases, a shorter, double-posted implant designed for use elsewhere might be employed, with its distal post (7) centered in the second molar — which receives the most lateral pressure — and its proximal (8) offset posteriorly within the first molar.

If two-post support would really prove superior in a short posterior span, two alternatives may be practical. Perhaps the ridge is wide enough to curve the proximal shoulder (9) of the implant away from the tooth, but only a truly experienced operator can coordinate the curve of both the socket and the implant so that the implant fits passively. Also, extreme bending to almost a right angle is not advisable. Bone dieback within the angle may create a weakened area around the proximal shoulder.

The more practical solution may be to reduce the length of the implant by removing an anterior leg. The cut edges must be smoothed and retapered (10). The posts of the remodeled implant can then easily be centered (11) under the crowns without intruding into the bicuspid's periodontium (12) .

Generally, the more teeth missing, the greater the problems in inserting posterior bladevents. The longer span often reflects more edentulous time, with its accompanying problems. When the molars and second bicuspid are missing, it is only occasionally possible to use the very sturdy, deep-bodied bladevent designs.

In posterior partially edentulous situations it may be necessary to reduce the post height of standard bladevents to assure occlusal clearance. The posts must be ground down until they no longer interfere with closure. This is done with a disk or stone, preferably outside the mouth prior to final seating, with the implant steadied by securing the post so that the neck is not overworked. The posts can also be reduced directly in the mouth immediately postinsertion without fear of loosening or dislodging the bladevent, a feature unique to this implant.

Problem Ridge:

Shallow and Narrow

A shallow ridge is usually a narrow ridge. The tendency in the posterior regions, as in the anterior, is for the buccal surface (1) to resorb more rapidly than do the palatal (2) or occlusal surfaces (3). Thus the typical resorption pattern is a thinning of

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