Long-term evaluation of overdentures retained by resilient telescopic crowns

For the evaluation of survival and success rates of resilient telescopic crown retained overdentures, 221 patient files with 263 overdentures on 538 abutment teeth were included in this retrospective analysis. All of the patients were treated in the Department of Prosthodontics of the University Medical Center Goettingen. The observation periods ranged from 3 to 179 months, with a mean observation period of 64.5 months (5.4 years). The results of the Kaplan-Meier analysis indicated an overdenture survival rate of 62% after 5 years, 38% after 8 years and 28% after 10 years. The overall success rates (complication-free survival) of the 263 overdentures were 13% after 5 years, 3% after 8 years and 1% after 10 years. The survival rate of the abutment teeth was 55% within a 5-year observation period and decreased to 34% after 8 years and 30% after 10 years of clinical function. A Cox-Regression analysis revealed that the number of the abutments significantly influenced the survival rates of the abutment teeth and the overdentures. Furthermore a statistical significance for the impact of the antagonistic support was demonstrated for the rate of base fractures: removable dental prostheses caused a lower probability for a fracture than fixed dental prostheses and natural teeth. Due to the high rate of complications, it can be postulated that the resilient support of the telescopic crown retained overdentures provides no advantages in relation to conventional overdentures supported by a maximum of three abutment teeth. The number of the abutment teeth remains to be a crucial factor for determining the long-term performance of resilient telescopic crown retained overdentures.2018-04-1