title: Epidemiologic evaluation of the outcomes of orthograde endodontic retreatment.
abstract: BACKGROUND
  Teeth undergoing initial endodontic therapy have a very high survival rate. Some teeth that continue to show signs of pathosis after the initial therapy will require nonsurgical (orthograde) retreatment. Outcome assessment of endodontic retreatment is crucial for appropriate case selection and treatment planning. However, reports on outcomes of orthograde endodontic retreatment performed by endodontists are limited in number, and the reported data vary. In this study, outcomes of orthograde endodontic retreatment performed on 4744 teeth were assessed during a period of 5 years.
  
  
  METHODS
  Data were obtained from retreatments that were performed by endodontists participating in the Delta Dental Insurance plan that insures approximately 15 million individuals in the USA.
  
  
  RESULTS
  Overall, 89% of teeth were retained in the oral cavity 5 years after the endodontic retreatment. Four percent of all teeth underwent apical surgery that occurred mostly within 2 years from completion of orthograde retreatment. Eleven percent of teeth were extracted at the end of the 5-year observation period.
  
  
  CONCLUSIONS
  It appears that orthograde endodontic retreatment yields high incidence of tooth retention after 5 years.
authors.affiliation: Division of Endodontics, Oral & Maxillofacial Surgery and Orthodontics, University of Southern California, Herman Ostrow School of Dentistry of USC, Los Angeles, California 90048-0641, USA. rsri@usa.net
authors.forename: Robert
authors.initials: R
authors.lastname: Salehrabi
authors.forename: Ilan
authors.initials: I
authors.lastname: Rotstein
mesh_terms: D001047:Apicoectomy / Q000706:statistics & numerical data; D006801:Humans; D007347:Insurance, Dental / Q000706:statistics & numerical data; D019233:Retreatment / Q000706:statistics & numerical data; D012189:Retrospective Studies; D012390:Root Canal Therapy / Q000706:statistics & numerical data*; D014081:Tooth Extraction / Q000706:statistics & numerical data; D016896:Treatment Outcome; D014481:United States