Single tooth implants 321

Fig. 8-34. An all-acrylic jacket processed over a hollow gold thimble was fabricated. Pink acrylic was also included above the labiogingival margin of the restoration in order to restore much of the gum tissue that had resorbed.

Fig. 8-35. Three pin implants were slowly drilled through the fibromucosal tissue and into the bone. Their apices diverged from one another as much as the anatomic land-marks allowed them.

Fig. 8-36. The protruding notched pin implants were fused with an acrylic core.

otherwise. In this case, to aid stabilization the crown restoration over the triplant was A-splinted to both neighboring teeth.

The patient, a young male colleague, originally had his right central incisor knocked out while playing football. After performing root canal therapy with the tooth out of the mouth, the tooth was re-implanted by his dentist. A few years later, the entire root resorbed (Fig. 8-32) and the remaining corona] portion of the tooth was removed (Fig. 8-33). An impression of the edentulous space was taken, and an all-acrylic jacket over a gold thimble was processed. The restoration also contained pink acrylic on its labiogingival aspect to replace the lost gingival tissue (Fig. 8-34).

Three implant pins were slowly driven into the bone through the fibromucosal tissue as deep and as far apart as possible (Fig. 8-35). The ends of the pins were then notched with a fissure bur to make them more retentive for the acrylic core (Fig. 8-36). When the core hardened, a soft mix of acrylic was

Fig. 8-37. The crown is cemented to the acrylic core with a loose mix of resin material.

placed inside the acrylic and gold thimble crown, which was cemented into position (Fig. 8-37). All excess acrylic was trimmed away, and the tooth was checked for proper occlusion. Then grooves were made with a small inverted cone bur on the lingual aspects of the acrylic crown and on the two neigh-boring teeth. With cold cure acrylic mixed to a loose consistency, two adapted and serrated gold wires were locked into position, thus stabilizing the implant. An x-ray was taken immediately after inserting and A-splinting the implant (Fig. 8-38, A).

Twenty-one months later another x-ray was taken (Fig. 8-38, B) . The implant crown was then separated from its A-splint (Fig. 8-39). The tooth was extremely loose after the splint was disassembled and was easily pulled out of the mouth with all three pins intact (Fig. 8-40) . The case was a failure. A triplant, even stabilized with an A-splint, should not have been attempted in this area. There is rarely enough bone here, and no amount of partial stabilization is adequate in such a situation.