title: A comparison of four root canal obturation methods employing gutta-percha: a computerized analysis of the internal structure.
abstract: The purpose of the present investigation was to compare the internal structure of gutta-percha for presence/absence of empty spaces when used in four different obturation methods: thermoplastic, chloroform-softened, thermomechanical, and warm lateral condensations. Each obturation was performed five times in a metal mold representing a root canal system. Following obturation the mold was disassembled and the gutta-percha was freeze-fractured at the 1.0, 3.5, and 6.5 mm levels as measured from the tip of the obturations. The fractured gutta-percha was placed in a scanning electron microscope, the image transferred to a computer, and converted to digital data. The results were subjected to statistical evaluation. The results demonstrated no difference between the obturation methods at the 1 mm level, however at the 3.5 mm level, thermomechanical condensation produced an internal structure characterized by a greater number of empty spaces (p < 0.0007). At the 6.5 mm level, thermomechanical condensation differed only from the chloroform-softened gutta-percha (p < 0.01).
authors.affiliation: Department of Endodontics, College of Dentistry, University of Illinois, Chicago.
authors.forename: E L
authors.initials: EL
authors.lastname: Jacobsen
authors.forename: E A
authors.initials: EA
authors.lastname: BeGole
mesh_terms: D000704:Analysis of Variance; D002725:Chloroform; D006171:Gutta-Percha / Q000737:chemistry*; D006358:Hot Temperature; D007090:Image Interpretation, Computer-Assisted; D008855:Microscopy, Electron, Scanning; D012389:Root Canal Obturation / Q000379:methods*
chemical_list: D002725:Chloroform; D006171:Gutta-Percha