Maxillary endosseous implant interventions 413

sions and bite registrations were taken so that three castings could be fabricated to fit over the remaining teeth (Fig. 10-91).

Because the lower teeth could interfere with the proper angulation of a straight handpiece and cause the bur to perforate the palate, a contra-angle was used. Spear-point burs were first used to penetrate the rnucosa, submucosa, and superficial alveolar bone. These were followed by various sized helical burs (Fig. 10-92). The tantalum vent-plants, which were non–self-tapping, were then screwed into holes made

Fig. 10-103. A cross-sectional occlusal film.

in the bone by specially designed and sized taps (Fig. 10-93).

After all the vent-plants had been inserted (Fig. 10-94), a wax interocclusal record of centric relation-ship and a full maxillary plaster index including the three copings and impressions of the implant shafts were taken. Duplicate shafts were set inside the plaster index, and the master stone model was poured and articulated with the lower cast. The gold framework was then completed in one segment (Fig. 10-95), and the acrylic teeth were processed to the gold (Fig. 10-96).

At the next visit, the upper full arch splint was tried in the mouth (Fig. 10-97) and cemented with oxyphosphate of zinc cement (Fig. 10-98). The lower full arch splint was also processed and cemented (Fig. 10-99).

Immediate postoperative radiographs included intraoral periapical radiographs (Fig. 10-100), a posteroanterior roentgenogram (Fig. 10-101), a lateral head roentgenogram (Fig. 10-102), and a cross-sectional occlusal film (Fig. 10-103).

A 6-year postoperative Panorex film reveals some areas of bone resorption caused specifically by the improper architectural design in these early models. However, no pain or mobility exists and the patient is extremely happy (Fig. 10-104).

Fig. 10-104. A 6-year postoperative Panorex roentgenogram reveals some bone loss resulting mainly from the earlier improperly designed vent-plants.