posts will then protrude into the central incisor and cuspid regions. The posterior extent of the socket must avoid the mental foramin (1). It may stop in front of the foramen, or—if the ridge is deep—extend over it, (2) .

Frequently the angle of the ridge on the lingual side of the incisor region (3) is less than that in the region of the molar area (4) if it should exhibit a deep submandibular fossa (4A) . This means that what may be an ideal inclination for the socket in the incisor region (5) threatens the lingual plate (6) in the molar 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 or slightly less (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,

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