Mandibular endosseous implant interventions 361

Fig. 9-90. A Panorex reveals all six implants. Since the prefabricated prosthesis had all acrylic pontics (which cannot be seen on radiographs) the retention bars and loops of the gold work make the prosthesis appear to have uneven margins.

down fashion while the acrylic is hardening. The bridge should never be left in the mouth to harden. Not only will it be almost impossible to remove, but the rough knife-like edges of the hardened acrylic can injure the soft tissues. Therefore the bridge must be hardened outside of the mouth and all excess acrylic trimmed and polished. Also, the holes must be made wider to compensate for the implant's lack of parallelism (Fig. 9-88) . The bridge is permanently seated with a hard cement (Fig. 9-89). A final x-ray is then taken (Fig. 9-90) .

Case 9

A full arch splint for a partially edentulous mandible using bilateral posterior implants

In this case only two lower cuspid teeth were present. From impressions and bites, two gold copings were cast to cover the cuspids, and two veneer crown castings were made to fit over the copings. A temporary acrylic splint was fabricated with a trench along the tissue-bearing surface of the free-end pontics to accommodate and support the implants (Fig. 9-91) .

The gold copings were cemented over the cuspid teeth, and the cuspid veneer castings were placed over the copings. An accurate wax bite and plaster index of the lower jaw were taken and articulated with the opposing model. From this the anterior quad-rant was cast and soldered together and a wax-up of their facings was accomplished.

The six-unit anterior splint with the wax facings was placed over the two cuspid copings and checked for accuracy and esthetics. The implants were set

Fig. 9-91. Two gold copings and two veneers are cast to fit over the only remaining cuspid teeth. A temporary full arch acrylic splint is also made.

into their positions and interchangeable gold copings placed over them. The interocclusal space was checked while the patient bit in centric occlusion to make sure that there was no interference from the copings (Fig. 9-92). An accurate wax interocclusal record of centric relation was then taken with the castings and copings in position.

A full lower plaster index was also made, pick-