Balanced insertion is essential to keep any bladevent design from being rocked in its socket and unnecessarily destroying bone. The asymmetrical shape of the sinus-circumventing blade must be compensated by atypical variations in making the socket. When the deeper end is distal, the bone tends to be firmer than the shallow proximal bone. To create a more balanced "feel" during seating, the deeper end is drilled to its entire depth, thus removing resistance in front of that leading edge. The shallow portion of the socket may not be drilled to its entire depth to leave greater resistance there.

In drilling the socket, the shallowest part of the ridge should be the guiding dimension. Its exact depth is determined from radio-graphs, then about 2-3 mm are subtracted as a safety margin. The resulting measurement is noted (8) and if so desired — marked on the bur with a rubber stop (9) .

The socket can be started at the most distal point, at least 3-4 mm in front of the hamular notch, and the bur run forward in a continuous sweep (10). The stop on the bur always keeps it below the deepest portion of the sinus, and working from back to front permits clear visualization of the operative site. Little resistance to the bur should be anticipated in the shallow zone.

In questionable situations, the socket should be started in the shallowest portion of the site, even if this is the more anterior point.

A shallow socket (11) is made slightly longer than the mesiodistal length of the bladevent. Then adjustments are made to accommodate the deeper end of the implant. The stop (12) on the bur is adjusted for the deepest part of the implant. The bur is sunk to the marker in the appropriate portion of the socket, and then started toward the shallower end — gradually being retracted. A few millimeters from the shallow end of the socket, roughly where the more anterior post will be set (13), the bur should run free in the previously drilled shallow groove.

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