title: [Survey of root canal curvature of anterior teeth from Chuang population].
abstract: OBJECTIVE
  To investigate the root canal curvature of permanent anterior teeth from Chuang population.
  
  
  METHODS
  245 anterior teeth from Chuang population were collected and examined by X-ray radiography both from labiolingual and mesiodistal directions. For 218 type I anterior teeth, degree of root canal curvature, radius of curvature and length of the curved part of root canal were measured by a special electronic vernier caliper according to Schneider's and Schäfer's method and the data obtained were analyzed.
  
  
  RESULTS
  Root canals of anterior teeth from Chuang population were mainly of type I. The number of type II, III, IV were about 13 in mandibular central and 12 in mandibular lateral incisors. The incidence of curvature in maxillary central incisors, lateral incisors, canines and mandibular central incisors, lateral incisors, canines were 40%, 80%, 77%, 65%, 66%, 73% in mesiodistal directions, 62%, 69%, 70%, 62%, 41%, 61% in labiolingual directions respectively. The most curvature was moderate and happened in apical third. The heaviest curvature occurred in maxillary canines in mesiodistal direction and mandibular canines in labiolingual direction. The shortest radius and length of curvature occurred in maxillary lateral incisors.
  
  
  CONCLUSIONS
  Root canal curvature of anterior tooth in Guangxi Chuang population is complex. The incidence of type II, III, IV is high in mandibular incisors.
authors.affiliation: Dept. of Conservative Dentistry, The Affiliated Stomatology Hospital of Tongji University, Shanghai 200072, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Liu
authors.forename: Shu-fang
authors.initials: SF
authors.lastname: Wang
authors.forename: Shou-liang
authors.initials: SL
authors.lastname: Zhao
mesh_terms: D002681:China; D003481:Cuspid; D003786:Dental Pulp Cavity; D019229:Dentition, Permanent; D006801:Humans; D007180:Incisor; D008334:Mandible; D012390:Root Canal Therapy