Discussion
Out of 189 implants nine were explant prematurely. Since all except for one exception were not yet prosthetically restored because of the too short implant duration (mean value 3.5 months), prosthetic restoration as possible cause for explantation is not discussed further in the present study. It is not new that failures occur primarily within the healing phase and this is described in many studies. Albrektsson et al. [4]even go so far as to start the assessment of the success of an implant only after the first year insitu, which would significantly improve the success statistics in the present study.
Seven customary implant systems were evaluated with regard to their clinical success in the publication by d‘Hoedt et al. [8]. The evaluation was based on the success criteria of the authors. Since the present study works with the same success criteria, the results can be compared especially well. In the one-year implant duration analysis according to Kaplan-Meier, all systems show with 87 to 100% a similarly good result compared with the zirconia implants examined in the present study (93%). If one includes additional success criteria (Jahn and d‘Hoedt) such as the sulcus depth, angular bone loss, periimplantary radiotranslucence, loosening and subjective patient assessments in the survival time analysis, the examined Z-Look3 zirconia implants with a probability of success after one year of 93% perform better than the IMZ (90%), Bonefi t(92%), ITI (75%), Frialit-2 (88%) and TPS (80%)systems. Only the examined Bränemark implants show in this evaluation with 100% a somewhat better result than zirconia implants.
Brocard et al. [6] still found in contrast to d‘Hoedt even after five years a probability of success of 95% for ITI implants made of titanium.