title: Three-year outcomes of apicectomy (apicoectomy): Mining an insurance database.
abstract: OBJECTIVE
  The outcome of apicectomy in clinical reality is supposed to be different compared to outcomes reported from clinical trials. The objective of this study was to measure the outcome of apicectomies under practice conditions by mining an insurance data base.
  
  
  METHODS
  This retrospective study was based on claims data of a major German national health insurance company (BARMER GEK). Through the company's data warehouse fee codes and treatment dates were accessible and allowed the tracing of clinical courses. Kaplan-Meier survival analyses for the target event 'extraction' were conducted for all teeth that underwent apicectomies within a 3 year period. Testing for differences among survival rates across groups was performed with the Log-Rank-test.
  
  
  RESULTS
  A total of 93,797 teeth in 77,636 patients could be traced after apicectomy. The cumulative 3-year survival rate was 81.6%. Anterior teeth showed a significantly higher survival rate of 84.0% compared to premolars (80.4%) and molars (80.2%). The survival rate in men (83.5%) was significantly higher than in women (80.6%). Analysis of survival by age revealed continuously declining survival rates with age (93.3% for subjects under 18 years of age to 75.6% for subjects over 84 years of age).
  
  
  CONCLUSIONS
  The 3-year outcomes of apicectomy were still acceptable for an intervention that is mostly conducted as a retreatment after failure of a preceding measure. However at a population level, the question remains to be answered whether other treatment options would potentially be more effective.
authors.affiliation: Department for Prosthetic Dentistry, Faculty of Medicine Carl Gustav Carus, Technische Universitaet, Dresden Fetscherstrasse 74, 01307 Dresden, Germany. Electronic address: Michael.Raedel@uniklinikum-dresden.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Raedel
authors.affiliation: AGENON, Gesellschaft für Forschung und Entwicklung im Gesundheitswesen mbH, Kaunstrasse 21, 14163 Berlin, Germany. Electronic address: ah@agenon.de.
authors.forename: Andrea
authors.initials: A
authors.lastname: Hartmann
authors.affiliation: AGENON, Gesellschaft für Forschung und Entwicklung im Gesundheitswesen mbH, Kaunstrasse 21, 14163 Berlin, Germany. Electronic address: bohm@agenon.de.
authors.forename: Steffen
authors.initials: S
authors.lastname: Bohm
authors.affiliation: Department for Prosthetic Dentistry, Faculty of Medicine Carl Gustav Carus, Technische Universitaet, Dresden Fetscherstrasse 74, 01307 Dresden, Germany. Electronic address: Michael.Walter@uniklinikum-dresden.de.
authors.forename: Michael H
authors.initials: MH
authors.lastname: Walter
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001047:Apicoectomy / Q000379:methods / Q000706:statistics & numerical data*; D002648:Child; D057225:Data Mining; D016208:Databases, Factual; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D007347:Insurance, Dental / Q000706:statistics & numerical data*; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012984:Software; D016896:Treatment Outcome; D055815:Young Adult
keywords: Apicectomy; Data mining; Endodontics; Oral surgical procedures; Survival analysis; Treatment outcome