338 Theories and techniques of oral implantology

Fig. 9-12. The implants are radiographed.

Fig. 9-10. The first vent-plant is then screwed into position using a ratchet. (From Linkow, L. I.: The radiographic role in endosseous implant interventions, Chron. Omaha Dent. Soc. 29 [10] :304-311, 1966.)

Fig. 9-11. The second vent-plant is inserted. (From Linkow, L. I.: The radiographic role in endosseous implant interventions, Chron. Omaha Dent. Soc. 29 [10]:304-311, 1966.)

by the preceding round bur. Another x-ray was taken (Fig. 9-9).

One of the helical burs was then removed, and in its place a helical bur of a larger diameter was inserted. The diameter of this second helical bur corresponded to that of the desired vent-plant. This bur was drilled into the bone parallel to the remaining helical bur and to the prepared crowns and x-rayed. The purpose of this x-ray, as well as others taken at different levels during the insertion of the taps and burs, was to ensure accurate placement. The remaining smaller helical bur was replaced by one of a larger diameter, and another roentgenogram was taken.

The appropriate vent-plant was then ready for insertion. One of the helical burs was removed, and

Fig. 9-13. The veneer castings are fitted over both bicuspid teeth. (From Linkow, L. I.: The radiographic role in endosseous implant interventions, Chron. Omaha Dent. Soc. 29 [10]:304-311, 1966.)

the first vent-plant was screwed into its hole (Fig. 9-10) and x-rayed. The remaining bur was then re-moved and the second vent-plant inserted (Fig. 9-11) . Both implants were radiographed (Fig. 9-12).

The castings were fitted over the prepared teeth

(Fig. 9-13), and copings of some sort   in this case

gold, although plastic ones may also be used   were
placed over the protruding implant shafts (Fig. 9-14).

A wax bite and plaster index were taken (Fig. 9-15), with the castings and copings included in the index (Fig. 9-16). (Sometimes copings are not necessary over the implants. Instead, the plaster index picks up the castings covering the natural tooth abutments and only the impression of the protruding implant shafts.) Duplicate size bronze or copper shafts were immediately placed in the index and the master