The Universal Subperiosteal Implant

Similarly, the technique for this procedure is similar to that of the unilateral procedure with several differences.

The reflection of the tissues are done on both sides of the arch instead of one. Also, and more important is that the tissues in the areas of the remaining anterior teeth must all be reflected downward to expose the entire symphysis and genial tubercles (1). Before the impression can be taken all the remaining teeth should be prepared for full crown restorations (2). This can be accomplished prior to or after the tissues are reflected. It is important, however, to be absolutely careful when separating the gingival tissues from the necks of the teeth so that minimal tissues are destroyed. With the entire mandible exposed and the teeth prepared a full mouth silicone impression is taken and the material moulded in the same manner as when taking the impression in a unilateral site. The interocclusal records of centric relation-ship is taken at the same time and with the same material (3). If a tray is preferred then the silicone impression is removed from the mouth, the stone model poured into it and the upper stone model set into the opposite side of the silicone impression and models are articulated (4). A thin acrylic tray is cold-cured directly over the accurate stone model (5) and can then be used as a tray for a rubber base impression material directly over the bone (6). Or, as I now more often do, an Omnivac tray is fabricated from the stone model, and used to support the rubber base impression. Making a prefabricated tray (7) from an impression of the soft tissues to be then used for taking the bone impression, is never accurate enough and too many adjustments of the tray must be done.

The tissues are sutured together and a temporary acrylic splint is carefully fitted over the prepared abutment teeth (8). Most of

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