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Purpose: The clinical performance of three- and four-unit fixed partial dentures (FPDs)
with frameworks made of yttria partially stabilized zirconia was determined after a mean
observational period of 84 months. Materials and Methods: Seventy-five patients
were treated with 99 posterior FPDs. Fifty-one specimens were veneered with an
experimental ceramic suitable for titanium and zirconia frameworks; 48 restorations
were veneered with a commercially available low-fusing ceramic optimized for zirconia
frameworks. All restorations were luted with zinc-phosphate cement. Statistical analysis
was performed according to Kaplan-Meier; potential risk factors were analyzed using
the Cox regression analysis. Results: Nineteen restorations failed completely: 12 due to
technical complications, 6 due to biologic complications, and 1 for unknown reasons.
The overall survival rate after 84 months was 83.4%. Thirty-two events required clinical
intervention for restoration maintenance, resulting in a time-dependent success rate of
57.9% after 84 months. Nineteen dropouts occurred during the follow-up time. None of
the evaluated factors showed an association with survival or success of the restorations.
Conclusions: After a mean observational period of 7 years, the survival and success
rates of zirconia-based posterior FPDs were inferior to those published for metalceramic
FPDs. The majority of failures were caused by technical complications (material
fractures). The main reasons for clinical intervention to maintain function were fractures
of the veneering ceramic and decementations. Int J Prosthodont 2013;26:164–171.
doi: 10.11607/ijp.3229
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