2 Theories and techniques of oral implantology

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Fig. 1-1. A, Spiral-shaft implants (Chercheve) with interchangeable gold copings. B, Various sizes of early designed vent-plant implants. C, A tripod implant, assembled. D, Various early designed blade implants.

abutments. The reason for selecting this type of case in illustrating spiral-shaft and vent-plants is that both of these implant designs require some sort of stabilization until they can take hold. Although they are initially secure when inserted properly, movements of the tongue, cheeks, and lips can loosen them before the bone heals. The temporary pros-thesis attached to the natural abutments protects the implants against dislodgment.

In illustrating the tripod implant, the restoration of a single tooth in the area of a maxillary sinus has been chosen. This implant also requires stabilization, and for the same reasons. Its importance, which is clearly indicated by the example chosen, is its use in cases where little alveolar bone exists between an anatomic landmark and the crest of the ridge.

The blade implant procedure will be described and illustrated with the installation of a unilateral fixed partial denture.

In discussing all of these cases, it will be assumed that the patient, his jaws, and his remaining teeth are in excellent health.

Spiral-shaft implants

The spiral-shaft implant consists of a solid square shaft approximately 2 mm. on each face and a hollow, double helical spiral part. The combined length of the implant can be varied to suit the amount of space in the individual patient's jaw. The square portion may range from 10 to 14 mm. long, and there may be from two to four spirals. It is important to remember that the spirals should be set into bone, well away from the crest of the ridge, for a