150 Theories and techniques of oral implantology

look back on Formiggini's implant and clearly see its flaws. Yet modifications of his ideas form the practical basis for most kinds of successful modern implants.

One major flaw was that the operator himself constructed the implant during the intervention procedure. This meant that no two implants were ever alike. Their suitability to the site depended upon the operator's skill in twisting the wire around itself while he tried to coordinate the implant he was making with the character of the site in which it was to be set. In the hands of an exceptionally skillful operator, the results might be good (Fig. 5-26). For most other operators, however, dealing with a

flexible wire implant proved more difficult than valuable. As if fashioning the wire weren't difficult enough, other problems arose. Bending a wire weak-ens it. Thus there was always a good chance of breaking the implant either during insertion or because of stress upon it.

Fig. 5-27 demonstrates better than words the good and bad features of Formiggini's implant. In A, a skillfully fashioned implant is shown in place. B shows a different implant, with a great deal of bone regrowth around its base. However, the implant has broken in the region of its first spire. D shows the implant during its extraction. The superficial spires

Fig. 5-28. Bone regrowth in a single tooth implant by Formiggini. The implantation is partially successful. A, The open socket; B, the implant soon after insertion; C, 8 months later; D, over 1 year later. The deeper spirals are surrounded by bone; however, soft tissue encapsulates the superficial spires. (From Chercheve, R.: Les implants endo-osseoux, Paris, 1962, Librairie Maloine.)