Objectives: The aim of this retrospective study was to evaluate the long-term outcomes of long-span fixed dental prostheses (LSFDPs) not meeting Ante's law. Method and Materials: This study is based on the data of 36 patients who received 41 LSFDPs. The mean survival time of the LSFDPs was calculated using the Kaplan-Meier technique. The influence of the factors (gender, localization, number of abutments, Kennedy Class, dentition of the opposing jaw) were analyzed (log-rank test and Cox regression; P .05). Results: During the observation period, 22.0% (n = 9) of the LSFDPs ceased to function. The calculated outcome probability after 3 years was 88.3%, and 57.4% after 5 years. The only significant difference in the mean survival time could be found in LSFDPs with two abutment teeth in comparison with LSFDPs with three and more abutment teeth. Although all of the patients were invited to an oral health and maintenance program regularly, only 13.8% attended. Conclusion: The results, taken together with data from the literature, indicate that the patient's compliance is a crucial factor in the successful implementation of a LSFDP, whereas other factors are of minor importance. Keywords: Ante's law, clinical study, fixed dental prosthesis, Kaplan-Meier analysis, prosthodontics, retrospective analysis