The groove is made slightly longer mesio-distally (9) than the length of the blade. Distally, it begins about 5 mm to 7 mm in front of the hamular notch (10) to avoid intruding beyond the posterior limits of the maxillary tuberosity. In addition to providing a safety margin, the 5-7 mm limit helps position the implant far enough forward so that its posterior post will not interfere with the ascending ramus.

The bladevent is bent to fit passively within the groove, tried in it, and the proper alignment of the posts estimated. The blade-vent is withdrawn, and the neck bent to parallel the posts with the other abutments and perpendicular to the dental arch.

Caution: When bending the neck, grasp with the pliers only that portion of the bladevent's body directly under the post (11). Clamping the entire body (12) will straighten the carefully curved implant.

The bladevent is tapped into bone until the bottom of its posts meet the crest of the ridge. Frequently, a double-headed inserting instrument (13) can be used in a good ridge: the bone is adequately dense and the socket angle not exaggerated. A finger on the palatal side (14) of the instrument will absorb some of the force, offsetting it labially.

The pointed seating instrument can be used when the angle is more acute, but care must be taken not to let the cheek slip and dislodge the instrument during insertion.

The Partially Edentulous Maxilla

A two-molar span provides comfortable room for only one single-posted bladevent — with its post centered under the second molar (1) and the distal shoulder (2) approaching the tuberosity. If the sinus drops mesially (3), a special sinus-circumventing bladevent (4) should be substituted to avoid penetrating the sinus.

Occasionally, a doubled-posted bladevent can be used, but cautiously. The anterior shoulder of the implant should not intrude into the periodontium (5) of the second biscuspid. It should re-main about 1 mm away.

To avoid the periodontium, it may be possible in a long arch to move the implant posteriorly. Its posts may protrude into the distal position (6) of the naturally bulky crowns. However, for near-natural looking restorations, they should not fall interproximally as they might if the distal shoulder of the implant were seated well into the tuberosity.

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