Prognosis for Abutment Teeth of Removable Dentures: A Retrospective Study

Abstract

This retrospective study evaluates the clinical success of conical crown-retained removable dentures. Ninety-seven patients were treated with 97 dentures at the University of Frankfurt, Department of Prosthodontics, between 1993 and 2000. The average observation period was 4.9 +/- 2.8 years. The dentures were supported by 445 natural abutment teeth. To evaluate the long-term success of the restorations, the variables abutment loss, tooth mobility, mean probing depths, and radiological bone loss were used. Data were obtained by one clinical examiner at baseline, by systematic evaluation of patient records, and at clinical re-examinations. Survival-time methods were used to analyze time-to-event data. Specifically, the Cox model with frailty term was applied to account for correlations between intra-patient survival data. Thirty abutment teeth had to be extracted during the observation period. Statistical analysis showed no significant effects of the variables tooth mobility (p= 0.42), mean probing depths (p= 0.23), and radiological bone loss (p= 0.59) on the time to tooth extraction. For the non-extracted abutment teeth significant changes during time for the variables tooth mobility (p < 0.0001) and radiological bone loss (p= 0.0240) were observed. Removable partial dentures retained by conical crowns have a favorable clinical prognosis.