title: Survival of teeth treated with cast post and cores: A retrospective analysis over an observation period of up to 19.5 years.
abstract: BACKGROUND
  Scientific data about the long-term survival of teeth treated with cast post and cores are scarce. Retrospective studies often use different target events for their analyses. A comparison is therefore complicated. For associated tooth-, jaw-, and patient-related factors little evidence exists as to their effect on survival.
  
  
  OBJECTIVE
  The purpose of this study was to extend the knowledge on the survival of teeth treated with cast post and cores for observation periods of more than 10 years. A decrease or increase in survival times according to the presence or absence of associated parameters needs to be evaluated.
  
  
  METHODS
  A retrospective evaluation was conducted of all cast post and cores inserted in 1 university clinic between January 1992 and June 2011. A Kaplan-Meier survival analysis was carried out by using extraction as the target event. The survival curves for different tooth types, the presence or absence of adjacent teeth, and the prosthetic restoration of the respective jaws were compared by using the log-rank test (α=.05). A Cox regression model was calculated for multivariate analyses.
  
  
  RESULTS
  A total of 717 cast post and cores for 343 patients were recorded. The mean survival time was 13.5 years. A statistically significant decrease in survival times was found for canines (11.9 years) and premolars (13.4 years) versus molars (14.1 years), no adjacent teeth (10.6 years) versus at least 1 adjacent tooth (13.8 years), and the restoration with removable dental prostheses (12.5 years) versus fixed dental prostheses and single crowns (13.9 years). The largest reduction in survival time was found for teeth being used as an abutment for a double crown-retained removable partial dental prosthesis (telescopic denture) (9.8 years). Tooth type and adjacent tooth status remained as significant variables within the multivariate Cox regression model.
  
  
  CONCLUSIONS
  Cast post and cores have an acceptable long-term survival time. Because different factors may influence survival, considering these factors in treatment planning may increase the long-term success of these restorations.
authors: Staff Dentist and Research Fellow, Department for Prosthetic Dentistry, Medical Faculty Carl Gustav Carus, Technical University Dresden, Germany. Electronic address: Michael.Raedel@uniklinikum-dresden.de.
authors: Michael
authors: M
authors: Raedel
authors: Former student and Research Fellow, Department for Prosthetic Dentistry, Medical Faculty Carl Gustav Carus, Technical University Dresden, Germany.
authors: Cliff
authors: C
authors: Fiedler
authors: Staff Dentist and Research Fellow, Department for Prosthetic Dentistry, Medical Faculty Carl Gustav Carus, Technical University Dresden, Germany.
authors: Stephan
authors: S
authors: Jacoby
authors: Professor and Head of the Division, Preclinical Training and Experimental Dentistry, Department for Prosthetic Dentistry, Medical Faculty Carl Gustav Carus, Technical University Dresden, Germany.
authors: Klaus W
authors: KW
authors: Boening
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001641:Bicuspid / Q000473:pathology; D003442:Crowns / Q000706:statistics & numerical data; D003481:Cuspid / Q000473:pathology; D000044:Dental Abutments / Q000706:statistics & numerical data; D003828:Denture, Overlay / Q000706:statistics & numerical data; D003830:Denture, Partial, Fixed / Q000706:statistics & numerical data; D003832:Denture, Partial, Removable / Q000706:statistics & numerical data; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008875:Middle Aged; D008963:Molar / Q000473:pathology; D011176:Post and Core Technique / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D016019:Survival Analysis; D013997:Time Factors; D014081:Tooth Extraction / Q000706:statistics & numerical data; D055815:Young Adult