Analysis of veneer failure of removable prosthodontics.
OBJECTIVE
This retrospective study aimed to analyse the failure rate of the facings of double crown-retained dentures.


METHODS
The clinical reports of 575 patients, who received double crown-retained removable dentures with a total of 1807 double crowns between 1984 and 2007, were included in the study. The 575 prostheses were attached to telescopic crowns using a friction fit (FF; n = 1999), conical crowns (CC; n = 61), or parallel-sided telescopic crowns with a clearance fit (CF; n = 315). Survival probabilities for the veneers were investigated using the Kaplan-Meier method; Cox regression analysis was carried out to determine the influence of the double crown used for retention, type of antagonist, and localisation.


RESULTS
Veneer failure occurred in 7.0% of FF, 27.9% of CC, and 4.4% of CF. The risk of veneer failure was 2.3 times higher for CC than for FF (p = 0.042); no significant differences were found between CF and FF (p = 0.363). No significant influences on the localisation of the denture (p = 0.534) or the type of antagonist (p = 0.341) were found.


CONCLUSIONS
CC-based double crowns have a higher risk of veneer failure than FF and CF, which may be due to high tensile stresses occurring in the cervical area of their outer copings.
Department of Prosthetic Dentistry, University Medical Center Regensburg, Regensburg, Germany. sebastian.hahnel@klinik.uni-regensburg.de
Sebastian
S
Hahnel
Ralf
R
Bürgers
Martin
M
Rosentritt
Gerhard
G
Handel
Michael
M
Behr
D003188:Composite Resins / Q000737:chemistry; D003442:Crowns; D000044:Dental Abutments; D003722:Dental Alloys / Q000737:chemistry; D018772:Dental Marginal Adaptation / Q000145:classification; D003764:Dental Materials / Q000737:chemistry; D017267:Dental Prosthesis Design; D019232:Dental Restoration Failure; D003801:Dental Veneers; D003781:Denture Retention / Q000379:methods*; D003828:Denture, Overlay; D003832:Denture, Partial, Removable; D005260:Female; D017276:Friction; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013499:Surface Properties; D016019:Survival Analysis
D003188:Composite Resins; D003722:Dental Alloys; D003764:Dental Materials