title: [Clinical evaluation on the root canal therapy bypassing intracanal separated instruments].
abstract: OBJECTIVE
  To study and evaluate the clinical effect of root canal therapy bypassing intracanal separated instruments.
  
  
  METHODS
  32 teeth were selected as the test group, from which the intracanal separated instruments couldn't be taken out, adopted the method of root canal preparation and obturation bypassing broken instruments. Meanwhile, 13 teeth were selected as the control group, in which the fractured instruments couldn't be taken out from root canal, and not be cured bypassing broken instruments. 30 teeth were selected as the conventional therapy group, in which the instruments were not fractured, the routine root canal therapy were adopted. The clinical efficacy of three groups were observed and evaluated through periapical index and clinical examination two years later.
  
  
  RESULTS
  After two years, 25 teeth were followed up in test group, the success rate of root canal therapy was 80.00%; 11 teeth were followed up in control group, the success rate of root canal therapy was 36.36%. All of the failed cases in two groups were the teeth with broken instruments in tip of root canal. In conventional therapy group, 22 teeth were followed up, and the success rate of root canal therapy was 90.91%.
  
  
  CONCLUSIONS
  Root canal therapy bypassing intracanal separated instruments is a feasible and effective method in treating the teeth with broken instruments.
authors.affiliation: Dept. of Stomatology, The Third Hospital of Peking University, Beijing 100083, China.
authors.forename: Yuan-gao
authors.initials: YG
authors.lastname: Li
authors.forename: Ji-chao
authors.initials: JC
authors.lastname: Wang
authors.forename: Xin
authors.initials: X
authors.lastname: Zhou
mesh_terms: D001641:Bicuspid; D006801:Humans; D007180:Incisor; D008963:Molar; D018915:Root Canal Preparation; D012390:Root Canal Therapy