title: Analysis of the gutta-percha filled area in C-shaped mandibular molars obturated with a modified MicroSeal technique.
abstract: OBJECTIVE
  To analyse the gutta-percha filled area of C-shaped molar teeth root filled with the modified MicroSeal technique with reference to the radiographic features and the C-shaped canal configuration.
  
  
  METHODS
  Twenty-three mandibular second molar teeth with C-shaped roots were classified according to their radiographic features as: type I--merging, type II--symmetrical and type III--asymmetrical. The canals were root filled using a modified technique of the MicroSeal system. Horizontal sections at intervals of 600 mum were made 1 mm from the apex to the subpulpal floor level. The percentage of gutta-percha area from the apical, middle and coronal levels of the radiographic types was analysed using the Kruskal-Wallis test. Complementary analysis of the C-shaped canal configurations (C1, C2 and C3) determined from cross-sections from the apical third was performed in a similar way.
  
  
  RESULTS
  No significant differences were found between the radiographic types in terms of the percentage of gutta-percha area at any level (P > 0.05): apical third, type I: 77.04%, II: 70.48% and III: 77.13%, middle third, type I: 95.72%, II: 93.17%, III: 91.13% and coronal level, type I: 98.30%, II: 98.25%, III: 97.14%. Overall, the percentage of the filling material was lower in the apical third (P < 0.05). No significant differences were found between the C-shaped canal configurations apically; C1: 72.64%, C2: 79.62%, C3: 73.51% (P > 0.05).
  
  
  CONCLUSIONS
  The percentage of area filled with gutta-percha was similar in the three radiographic types and canal configuration categories of C-shaped molars. These results show the difficulty of achieving predictable filling of the root canal system when this anatomical variation exists. In general, the apical third was less completely filled.
authors.affiliation: Department of Endodontics, Dental School of Bauru, University of São Paulo, Brazil. ronaldordinola@usp.br
authors.forename: R
authors.initials: R
authors.lastname: Ordinola-Zapata
authors.forename: C M
authors.initials: CM
authors.lastname: Bramante
authors.forename: I G
authors.initials: IG
authors.lastname: de Moraes
authors.forename: N
authors.initials: N
authors.lastname: Bernardineli
authors.forename: R B
authors.initials: RB
authors.lastname: Garcia
authors.forename: J L
authors.initials: JL
authors.lastname: Gutmann
mesh_terms: D001729:Bismuth / Q000627:therapeutic use; D002126:Calcium Hydroxide / Q000627:therapeutic use; D003722:Dental Alloys; D003786:Dental Pulp Cavity / Q000000981:diagnostic imaging / Q000473:pathology*; D006171:Gutta-Percha / Q000737:chemistry / Q000627:therapeutic use*; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008334:Mandible; D008963:Molar / Q000000981:diagnostic imaging / Q000473:pathology*; D009532:Nickel; D011859:Radiography; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000627:therapeutic use*; D012388:Root Canal Irrigants / Q000627:therapeutic use; D012389:Root Canal Obturation / Q000295:instrumentation / Q000379:methods*; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D013499:Surface Properties; D014025:Titanium; D019227:Tooth Apex / Q000000981:diagnostic imaging / Q000473:pathology
chemical_list: D003722:Dental Alloys; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; C080620:Sealer 26; C040654:titanium nickelide; D009532:Nickel; D006171:Gutta-Percha; D014025:Titanium; D012973:Sodium Hypochlorite; D002126:Calcium Hydroxide; D001729:Bismuth