Frequently the angle of the ridge in the incisor region (3) is greater than that in the region of the first bicuspid (4). This means that what may be an ideal inclination for the socket in the incisor region (5) threatens the palatal plate (6) in the bicuspid region! The operator must scan the entire implant site before he begins drilling, and select the angle suitable to the entire site.

Caution: When drilling the groove, always maintain a continuous angle to the horizontal plane. Do not make a twisted socket. Adapting an implant to it is too difficult.

The socket is gradually deepened. In dense bone, the depth to be drilled (7) at least equals the height of the bladevent, measured to the bottom of its post (8) .

If the bone is particularly cancellous, the socket is made only as deep as the bladevent's shoulder (9). The implant's leading edge (10) will break with little trauma the few fragile bony bridges under them, leaving intact bone between the lowermost portion of the implant (11) .

The bladevent is compared with the socket, and the amount of curvature (12) estimated. Two cone socket pliers (13) are used to bend the bladevent (14) until it fits the socket passively.

The leading edge of the bladevent should slip easily into the groove without binding on either end (15) of the socket. Again, it is better to gradually bend the implant to the correct curvature, checking it with the curve of the socket, than to work the metal back and forth.

Manual pressure (16) should be adequate to lodge the implant one or two millimeters in the socket to check post alignments with other abutments. With pliers, the neck (17) of each post is bent gradually to the appropriate angle (18). After all post adjustments have been made, it is time for final seating.

A double-headed seating instrument (19) is appropriate when the posts are either aligned or nearly aligned with the axis of the socket. The head fits over both posts, and aids in delivering simultaneous, equally distributed force to seat the implant. With an assistant's finger supporting the labial crest (20), the implant is tapped until the bottom of its posts sit on the alveolar crest.

If the implant does not seat smoothly, or if one end requires more force to seat or will not seat at all (21), remove the implant and check the socket with the special channel curette (22). Make adjustments, if necessary, and re-insert.

If the difficulty results from denser bone in one area, do not widen the socket in the denser area. Simply concentrate more force

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