Because an implant-supported restoration will not be tissue-borne, many of the problems arising from a tissue-bearing appliance are obviated, thus the implantologist can ignore a great many morphologic features that obstruct the proper fitting of a conventional denture. The implant-borne restoration will not impinge on a shallow sulcus or provoke a sensitive palatal condition—to name but a few impediments.

Usually more often in the maxillae than the mandible, excision or degloving of excessive soft tissue, generally in the tuberosity must be done when it interferes with the closure.

In the mandible sometimes the tissue covering a knife-edge becomes troublesome as a conventional denture presses on it. It makes implant insertion difficult, but it is alleviated by removing several millimeters of the spiny bone, thus widening and flattening the occlusal table, making it possible to insert blade implants. If a subperiosteal implant is the choice, then the tissue should be sutured closed, the denture relined and at least six months should elapse before initial surgery.

Most often, oral surgeons will do partial thickness flaps in order to reduce tissue to accommodate removable dentures. How-ever, in implantology a full tissue flap should always be used to ex-pose the bone without the periosteum attached, either for the direct insertion for a blade implant or for a direct bone impression for a subperiosteal implant. The tissue can always be degloved at the time the implant is inserted if the tissue interferes in anyway with the protruding implant post or the intermaxillary space that exists.

Alveoplasty

In most situations minor alveoplasty can be done at the time of implant insertion if an endosteal blade is employed. Removal of sharp bony spicules, retained roots, undercuts due to overhanging alveolar crests, etc., can be done, during the same visit the blades are inserted. One can go directly into the open sockets using socket blades or can avoid some of these areas. However, if a subperiosteal implant is used, grooves can be made in both cuspid, bicuspid, lateral or even central incisor areas across the crest labiolingually that just had the alveolectomy. These grooves should be from 3 to 4 mm. deep to support the crossover struts that will support the neck of the subperiosteal implant. Grooves should never be made across the posterior crest since it usually is

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