Double-crown-retained removable dental prostheses: a retrospective study of survival and complications.
BACKGROUND
Research data are scarce on double-crown-retained removable dental prostheses. In double-crown-retained removable dental prostheses, crown-like copings are definitively cemented to the abutment teeth and serve as prosthesis attachments.


OBJECTIVE
The purpose of this study was to evaluate the survival of double-crown-retained removable dental prostheses in use for 7 years and to determine their most common complications.


METHODS
A retrospective analysis was conducted to investigate the clinical outcome of 117 prostheses in 86 patients with 385 abutment teeth. Thirty-two telescopic-crown-retained removable dental prostheses, 51 conical-crown-retained removable dental prostheses, and 34 resilient telescopic-crown-retained overdentures were clinically reexamined by 1 investigator. Prosthesis success was defined as survival without severe complications (abutment tooth extraction). Statistical analyses were performed with Kaplan-Meier modeling and Cox regression (α=.05).


RESULTS
Minor complications, for example, the decementation of primary crowns (34.2%), failure of the veneer of secondary crowns (11.1%), fracture of the denture base (17.1%), and the need for relining (12%), were common. Cumulative prosthesis survival for all types of prostheses was 93.8% after 7 years. After the same period, prosthesis success was 90% for telescopic-crown-retained removable dental prostheses and 78.5% for conical-crown-retained removable dental prostheses and resilient telescopic-crown-retained overdentures.


CONCLUSIONS
The medium-term double-crown-retained removable dental prosthesis survival found in this retrospective investigation appears acceptable. When bearing in mind the limits of this study, this kind of prosthesis might be a viable treatment option for patients with a reduced dentition. However, more laboratory and clinical research is necessary to reduce the incidence of minor complications and confirm the present in vivo results in larger patient groups.
Assistant Professor, Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany. Electronic address: FranzS.Schwindling@med.uni-heidelberg.de.
Franz Sebastian
FS
Schwindling
Private practice, Mering, Germany.
Britta
B
Dittmann
Professor and Chair, Department of Prosthodontics, Heidelberg University Hospital, Heidelberg, Germany.
Peter
P
Rammelsberg
D000368:Aged; D000369:Aged, 80 and over; D002484:Cementation; D003442:Crowns; D000044:Dental Abutments; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D003801:Dental Veneers; D003819:Denture Bases; D003823:Denture Rebasing; D003781:Denture Retention; D003824:Denture, Complete; D003828:Denture, Overlay; D003832:Denture, Partial, Removable; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016019:Survival Analysis; D016896:Treatment Outcome