title: A prospective cohort study of endodontic treatments of 1,369 root canals: results after 5 years.
abstract: OBJECTIVE
  The purpose of this prospective study was: 1) to follow-up a large number of endodontic treatments performed by a single operator, periodically checked over a 5-year period; and 2) to correlate outcome to a number of clinical variables.
  
  
  METHODS
  This prospective study included all consecutive cases during the selected time period. All cases were followed regularly for a 5-year period. At the 5-year end point of the study, 470 patients with 816 treated teeth and with 1,369 treated root canals were available for evaluation.
  
  
  RESULTS
  The overall rate of success among the 816 teeth/1,369 root canals available for evaluation was 88.6%/90.3%. The success rate for 435 teeth/793 root canals undergoing vital pulp therapy was 91.5%/93.1%. Teeth/root canals with necrotic pulp but without detectable periapical bone lesion were successfully treated in 89.5%/92.3%. If the pulp necrosis was complicated by apical periodontitis, the success rate fell to 82.7% for the teeth and 84.1% for the root canals (P = .037). Teeth with periapical lesion <5 mm had a success rate of 86.6%, and in cases where the lesion was ≥ 5 mm the rate of success was 78.2%.
  
  
  CONCLUSIONS
  More severe disease conditions negatively affects outcome. An optimal working length was identified. Excess of root canal filling material decreases success. Infected pulp space should be treated with an effective intracanal dressing. The quality of the coronal restoration or the placement of intracanal post retentions does not affect treatment outcome.
authors.affiliation: Division of Endodontology, School of Dental Medicine, University of Connecticut, USA.
authors.forename: Domenico
authors.initials: D
authors.lastname: Ricucci
authors.forename: John
authors.initials: J
authors.lastname: Russo
authors.forename: Michael
authors.initials: M
authors.lastname: Rutberg
authors.forename: Josef A
authors.initials: JA
authors.lastname: Burleson
authors.forename: Larz S W
authors.initials: LS
authors.lastname: Spångberg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002648:Child; D015331:Cohort Studies; D003751:Dental Fistula / Q000628:therapy; D018772:Dental Marginal Adaptation; D003790:Dental Pulp Necrosis / Q000628:therapy; D003793:Dental Restoration, Permanent / Q000592:standards; D012534:Dental Scaling / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006171:Gutta-Percha / Q000627:therapeutic use; D006801:Humans; D008297:Male; D008875:Middle Aged; D010485:Periapical Periodontitis / Q000628:therapy; D011176:Post and Core Technique; D011446:Prospective Studies; D011672:Pulpotomy / Q000592:standards; D016300:Radiography, Bitewing; D019233:Retreatment; D012387:Root Canal Filling Materials / Q000009:adverse effects / Q000627:therapeutic use; D012388:Root Canal Irrigants / Q000627:therapeutic use; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods / Q000592:standards; D012390:Root Canal Therapy / Q000592:standards*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D006171:Gutta-Percha