Anterior Implantations

For purposes of implant insertion, the anterior region is that portion of the dental arch in front of the maxillary sinus. Because the most anterior extent of each sinus varies, the length of this region also varies. In most cases, the anterior region extends from cuspid to cuspid. Occasionally, the region reaches posteriorly into the second bicuspid area. However, this is rare because pneumatization and expansion of the sinus up to the canine pillar generally accompany the loss of teeth bordering the sinus.

The location and size of the maxillary sinus also varies commonly in the right and left maxillae. Consequently, the distance between the most anterior extent of the sinus and the midline may differ in each maxilla, making the bone available for implantation asymmetrically long on each side of the midline.

The three major landmarks in the anterior regions are the midline, the nasal cavity or vestibulum, and the incisive (anterior palatine) foramen. The extent to which these are troublesome depends upon the character of the ridge. Generally, the more bone the ridge has, the greater the safety margin between implant site and the nondental landmark.

Good Ridge

A good anterior ridge is wide labio-palatally with a slight labial concavity, and deep with relatively dense bone. The ridge

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