CAD/CAM Magazine

treated dentally, or only with extreme difficulty, owing to unfavourable placement in the jawbone until the dental master model has been created by the dental technician after casting or after the check-bite at the very latest. “Plaster is incorruptible!”. This conclusion, at- tributed to Freiburg dental surgeon Prof Eschler, was deliberately kept trivial; however, it is simply and utterly true. The dental master model shows the realities concerning placement of the implant, itsaxis,alsowithregardtoabutmentteeth,andthe transition to the gingiva. _Exemplary patient cases Our report will demonstrate, based on a few exemplary patient cases, the solution possibilities, but also the limits of implant-prosthetic trou- bleshooting—especially in terms of achieving a sustainable result for patient, dentist and dental technician. _Unidentified jaw misalignment (Figs. 1–8) Theproblem Two years ago, a male patient (in his mid-70s) had received two implants in the maxilla, followed by treatment with telescopes and a partial pros- thesis. The patient stated that “the work did not agree with him right from the start”. Aside from functional problems, he disliked the fact that the maxillary front teeth were not visible even when he opened his mouth half-way. Justbylookingatthemaxillaryprosthesisitwas easy to notice the metal portions of the prosthesis, which were placed extremely palatinally, showing through. An examination of the oral cavity re- vealed a considerable discrepancy between the implant placement and the axis of the plastic front teeth! Oursolution A wax-up marked the beginning of the actual treatment. It was modified until the patient was satisfied with the placement of his teeth and his subsequent appearance. Based on the results of thistreatmentplanning,wewereabletodetermine which position and alignment would be required fortwoadditionalimplants(distallyoftheexisting ones). This in turn resulted in the creation of a drilling template, which was used during the insertion of the two additional artificial abutment teeth. After osseointegration of these two implants in regions #14 and 24, the new partial prosthesis (now sup- ported by four implants (two existing and two new ones) was produced and integrated step by step. Aside from cases like the one mentioned above, whichareusuallytheresultofdesignerrorsand/or Figs. 5 & 6_After interdisciplinary planning between dental technician and dentist, two additional distally located implants were inserted; the four artificial abutment teeth each received a telescopic crown. We used individual insertion keys to facilitate incorporation of the telescopes. Fig. 7_Initial X-ray image with two implants (treated with telescopes) in the maxilla. Fig. 8_Condition after the increase of abutment teeth in the maxilla, each inserted distally of the previous implants. I 19 clinical technique _ implant-prosthetic troubleshooting I CAD/CAM 2_2011 Fig. 8Fig. 7 Fig. 6Fig. 5