title: [Root canal curvature in chinese mandibular permanent incisors].
abstract: OBJECTIVE
  To investigate the root canal curvature in Chinese mandibular permanent incisors.
  
  
  METHODS
  Two hundred and ninety nine Chinese mandibular permanent incisors were included in this study. The root canals were inserted with stainless steel 15# K files, and then taken radiography from the facial and proximal view by X-ray paralleling technique. Canal curvatures were evaluated by measuring the angle, the radius of the curvatures, and the length of the curved part of the canal. Based on the curved angle and the shape of curved canals, the root canals were classified.
  
  
  RESULTS
  The curved angle, radius, and the curved canal length was 5.28 degrees +/- 5.52 degrees, 16.19 mm +/- 12.38 mm, 4.10 mm+/-2.01 mm, respectively in the facial view; 9.99 degrees +/- 5.84 degrees, 18.86 mm +/- 9.71 mm, 3.27 mm +/- 2.39 mm, respectively in the proximal view. The prevalence of straight, light, moderate, and serve curved root canals in mandibular permanent incisors was 15.7%, 66.9%, 16.7%, and 0.7%, respectively (P<0.05) based on the curved angle. The prevalence of straight, L shape, and S shape curved root canals was 7.7%, 50.5%, and 41.8%, respectively (P < 0.05).
  
  
  CONCLUSIONS
  Most of the root canals in mandibular permanent incisors are curve.
authors.affiliation: Key. Laboratory of Oral Biomedical Engineering Ministry of Education, Sichuan University, Chengdu 610041, China.
authors.forename: Ding-Ming
authors.initials: DM
authors.lastname: Huang
authors.forename: Hong-Xia
authors.initials: HX
authors.lastname: Luo
authors.forename: Qian
authors.initials: Q
authors.lastname: Liu
authors.forename: Guang-Ning
authors.initials: GN
authors.lastname: Zheng
authors.forename: Xue-Dong
authors.initials: XD
authors.lastname: Zhou
mesh_terms: D003786:Dental Pulp Cavity; D006801:Humans; D007180:Incisor; D008334:Mandible; D012390:Root Canal Therapy; D013193:Stainless Steel
chemical_list: D013193:Stainless Steel