title: Root canal morphology and variations in mandibular second molar teeth of an Indian population: an in vivo cone-beam computed tomography analysis.
abstract: OBJECTIVE
  This study aims to investigate the root canal morphology of permanent mandibular second molars of an Indian population in vivo using cone-beam computed tomography (CBCT) images.
  
  
  METHODS
  CBCT images (n = 983; males = 489, females = 494) of untreated, completely developed permanent mandibular second molar teeth were examined. CBCT scans were acquired as part of diagnosis and treatment planning for treatments unrelated to the present study. The number of roots and root canals were recorded. Canal configuration was classified based on Vertucci's and Fan's classifications.
  
  
  RESULTS
  The most common configuration was two-root (79.35%) and three-root canals (53.50%). The incidence of three-rooted molars was 7.53%, whereas 13.12% of the studied teeth studied have fused roots with C-shaped canals. The predominant canal morphology in the mesial roots was Vertucci's type IV (45.17%), followed by type II (32.55%), type I (7.23%), type V (1.02%), and type III (0.91%). The distal root in contrast showed type I (61.14%) as the predominant canal configuration, followed by type II (18.21%) and type IV (7.53%). The incidence of three-rooted molars was higher in males (n = 55; 5.59%) than in females (n = 19; 1.94%) (p < 0.01). The canals in the extra roots exhibited type I (100%) root canal morphology. In teeth with C-shaped root canal (13.12%), the variations in the coronal, middle, and apical third ranged from C1 to C4.
  
  
  CONCLUSIONS
  Root canal systems of the mesial roots of mandibular second molars of the study population demonstrated a high degree of variability. While three roots were rare, there was a sexual predisposition. Fused roots with C-shaped canals were rare and demonstrated significant variations from the coronal to apical third.
  
  
  CONCLUSIONS
  Root canal morphology can demonstrate variations based on race and sex of patients. Clinicians must always consider the possible variations to ensure successful endodontic treatment.
authors.affiliation: Department of Conservative Dentistry and Endodontics, Nair Hospital Dental College, Mumbai, Maharashtra, India. ajinkya@drpawars.com.
authors.forename: Ajinkya Mansing
authors.initials: AM
authors.lastname: Pawar
authors.affiliation: Department of Conservative Dentistry and Endodontics, Government Dental College and Hospital, Mumbai, Maharashtra, India.
authors.forename: Mansing
authors.initials: M
authors.lastname: Pawar
authors.affiliation: Department of Endodontology, The Goldschleger School of Dental Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: Anda
authors.initials: A
authors.lastname: Kfir
authors.affiliation: Department of Conservative Dentistry and Endodontics, Terna Dental College and Hospital, Navi Mumbai, Maharashtra, India.
authors.forename: Shishir
authors.initials: S
authors.lastname: Singh
authors.affiliation: Department of Oral Medicine and Radiology, Nair Hospital Dental College, Mumbai, Maharashtra, India.
authors.forename: Prashant
authors.initials: P
authors.lastname: Salve
authors.affiliation: Department of Dentistry, Sir H N Reliance Foundation Hospital, Mumbai, Maharashtra, India.
authors.forename: Bhagyashree
authors.initials: B
authors.lastname: Thakur
authors.affiliation: Discipline of Endodontics, Faculty of Dentistry, University of Hong Kong, Hong Kong, Hong Kong.
authors.forename: Prasanna
authors.initials: P
authors.lastname: Neelakantan
mesh_terms: D000328:Adult; D063405:Anatomic Variation; D054893:Cone-Beam Computed Tomography / Q000379:methods*; D005260:Female; D006801:Humans; D007194:India; D008297:Male; D008334:Mandible; D008963:Molar / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D014092:Tooth Root / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*
keywords: Anatomy; CBCT; Mandibular second molars; Morphology; Root canal