title: Root and canal morphology of Thai mandibular molars.
abstract: OBJECTIVE
  To investigate the root and canal morphology of 351 mandibular permanent molars collected from an indigenous Thai population.
  
  
  METHODS
  The cleaned teeth were accessed, the pulp dissolved by sodium hypochlorite under ultrasonication and the pulp system injected with Indian ink. The teeth were rendered clear by demineralization and immersion in methyl salicylate. The following observations were made: (i) number of roots and their morphology; (ii) number of root canals per tooth; (iii) number of root canals per root; (iv) root canal configuration in each root using Vertucci's classification, with additional modifications; and (v) presence and location of lateral canals and intercanal communications.
  
  
  RESULTS
  Of 118 mandibular first molars, 13% had a third disto-lingual root. In three-rooted teeth, 80% of the main distal roots and 100% of the disto-lingual roots had type 1 canal systems. Of 60 mandibular second molars, 10% had C-shaped roots, the majority of which had type 1 (33%) or type IV (33%) canal systems. Of 173 third molars, 68% had two separate roots, 20% had fused roots and 11% had a single C-shaped root; the majority had two canals (61%).
  
  
  CONCLUSIONS
  This study suggests that Thai molars exhibit features of both Caucasian and Chinese teeth.
authors.affiliation: Department of Conservative Dentistry, Eastman Dental Institute for Oral Health Care Sciences, University College London, UK. K.Gulabivala@eastman.ucl.ac.uk
authors.forename: K
authors.initials: K
authors.lastname: Gulabivala
authors.forename: A
authors.initials: A
authors.lastname: Opasanon
authors.forename: Y L
authors.initials: YL
authors.lastname: Ng
authors.forename: A
authors.initials: A
authors.lastname: Alavi
mesh_terms: D044466:Asian People; D002244:Carbon; D004396:Coloring Agents; D003648:Decalcification Technique; D003786:Dental Pulp Cavity / Q000033:anatomy & histology*; D005006:Ethnicity; D005404:Fixatives / Q000737:chemistry; D006801:Humans; D008334:Mandible; D008963:Molar / Q000033:anatomy & histology*; D012459:Salicylates / Q000737:chemistry; D012973:Sodium Hypochlorite / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D013785:Thailand; D014092:Tooth Root / Q000033:anatomy & histology*; D044465:White People
chemical_list: D004396:Coloring Agents; D005404:Fixatives; D012459:Salicylates; D012997:Solvents; C028433:chinese ink; D002244:Carbon; D012973:Sodium Hypochlorite; C033069:methyl salicylate