title: Effect of varying the depth of heat application on the adaptability of gutta-percha during warm vertical compaction.
abstract: The purpose of this study was to compare the adaptability of gutta-percha after varying the depth of heat application in the obturation of a set of standard root canals. A split-tooth model was constructed using a human maxillary central incisor. The root canal was cleaned and shaped using a step-back preparation to a size #60 FlexOFile at the working length (WL). Five shallow depressions were produced on the root canal wall. Twenty obturations without sealer were performed for each technique (thermoplasticized injectable (TI), lateral condensation, and warm vertical compaction (WVC) with heat applications at 3, 4, 5, and 7 mm from the WL). After each obturation the model was separated and the mesial and distal sides of each obturation were examined and videotaped at x 32 magnification. The quality of the obturation was graded based on the replication to the WL, replication of the artificial depressions, surface adaptation, and homogenicity of the gutta-percha. The Kruskal-Wallis analysis and the Student-Newman-Keuls tests indicated that all the techniques were significantly different from each other (p < 0.05) except for the TI group versus the WVC group with the heat application to within 3 mm from the WL (p > 0.05). The TI technique was ranked best followed by the WVC with heat applications at 3, 4, 5, and 7 mm. The lateral condensation technique received the lowest ranking.
authors.affiliation: Department of Endodontics, School of Dentistry, Medical College of Georgia, Augusta 30912-1244, USA.
authors.forename: R S
authors.initials: RS
authors.lastname: Smith
authors.forename: R N
authors.initials: RN
authors.lastname: Weller
authors.forename: R J
authors.initials: RJ
authors.lastname: Loushine
authors.forename: W F
authors.initials: WF
authors.lastname: Kimbrough
mesh_terms: D000704:Analysis of Variance; D003786:Dental Pulp Cavity / Q000648:ultrastructure; D006171:Gutta-Percha / Q000737:chemistry / Q000627:therapeutic use*; D006358:Hot Temperature; D006801:Humans; D007180:Incisor; D007267:Injections; D011312:Pressure; D012387:Root Canal Filling Materials / Q000737:chemistry / Q000627:therapeutic use*; D012389:Root Canal Obturation / Q000295:instrumentation / Q000379:methods*; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D013499:Surface Properties; D014743:Videotape Recording
chemical_list: D012387:Root Canal Filling Materials; D006171:Gutta-Percha