370 Theories and techniques of oral implantology

Fig. 9-118. The mesostructure is fitted over and into the internally threaded implant shafts. (From Linkow, L. I.: Internally threaded endosseous implants, Dent. Concepts 10:16-20, 1967.)

Fig. 9-119. The superstructure is then fitted over both mesostructures.

then screwed into the implants. With the same mix, the superstructure was seated. After the mixture hardened, the excess was removed (Fig. 9-121) . The patient's mouth was once more checked for any prematurities or interferences in occlusion, then the four set screws secured the superstructure to the mesostructure (Fig. 9-122) .

Patients usually do not mind the silver color of the four set screws. For those that do, the screws may be set below the occlusal surfaces of the crowns and covered with acrylic. To remove the bridge, the shallow acrylic coverings should be drilled out. Proper occlusion is most important, as always (Fig. 9-123).

The entire case may be summarized with radio-graphs. Fig. 9-124 shows the four implants in the mandible. Fig. 9-125 shows the mesostructure over the implants and Fig. 9-126, the superstructure screwed to the mesostructure.

Case 13

Precision fitted denture for a partially edentulous mandible using anterior vent-plants

Sometimes, in order to rnore perfectly balance the occlusal forces and to prevent tipping of a full denture, implants are placed on one side of the mid-line to complement the natural teeth on the other side. In this case, two vent-plants were planned to