Double Crown-retained Removable Prostheses Supported by Implants or Teeth and Implants, a Long-term Clinical Retrospective Evaluation.

OBJECTIVES: The objective of this retrospective clinical study was to investigate the survival rates and complications of implant (I) or tooth-implant (TI) retained prostheses and abutments (teeth, implants) over a mean observation period of 11.26 years. The study also aimed to analyze the differences and complication rates between implant retained double crown removable dental prostheses (I-DC-RDPs) versus tooth-implant retained double crown removable dental prostheses (TI-DC-RDPs).

MATERIAL AND METHODS: We reviewed clinical data of 110 non-smokers (mean age = 53.9 years) who received DC-RDPs in maxillary or mandibular arches. 153 teeth and 508 implants were used to restore partially edentulous (PE; TI-DC-RDPs; n = 53) and completely edentulous arches (CE; TI-DC-RDPs; n = 57). Two designs of the distal extension were used: cantilevers (CAN) and saddles (SAD). Restorations were examined for abutment survival, mechanical or biological complications.

RESULTS: The 10-year survival rates were 99.3% (95% CI, 95.4-99.9%) for teeth and 99.3% (95% CI, 97.5 - 99.7%) for implants. The cumulative rates of TI- and I-RDPs free of technical complications were 77% and 86%, respectively. The risk of complications was not significantly different between CAN and SAD sub-groups of I-RDPs (p > .05). However, for TI-RDPs, technical complication risk was significantly higher in SAD type compared with CAN restorations (p = 0.02).

CONCLUSIONS: I- and TI-DC-RDPs seem to be recommendable for restoration of completely or partially edentulous arches. The technical and biological complication rates were lower for I-DC-RDPs in the CE arches than for TI-DC-RDPs in the PE arches. Regarding the RDP design, CAN prostheses produced significantly fewer technical complications than did SAD prostheses.