title: Photomicrographic evaluation of the apical sealing capacity of three types of gutta-percha master cones: an in vitro study.
abstract: The purpose of this study was to compare the apical sealing capacity of three types of gutta-percha master cones of the same apical size and different tapers following root canal preparation with nickel-titanium ProTaper Universal rotary instruments and microstructural replication with System B and Obtura III. Thirty extracted human incisors having one single straight root canal (type I Weine) were instrumented with rotary ProTaper to an F3 (30/.09) and gauged to confirm a final apical size of #30. Teeth were divided into three groups (n = 10) to be obturated as follows: Group 1: master cone Meta 0.06 taper/AH Plus, Group 2: master cone fine-medium Autofit 0.08 taper/AH Plus, and Group 3: master cone ProTaper F3 0.09 taper/AH Plus. The chosen technique was the continuous wave of compaction (System B and Obtura III). Teeth were embedded in acrylic and incrementally reduced at 0.5 and 1.0 mm from the apical foramina in a grinding machine for metallographic samples. Sections were examined and digitally photographed under a metallographic optical microscope in normal and polarized light and the images were processed. The total cross-sectional area of the root canal, the gutta-percha/sealer/voids' areas were quantified for each sample and statistically compared using one-way ANOVA and Kruskal-Wallis tests. No statistically significant differences between groups were observed (P > 0.05); however, the mean percentage of the gutta-percha-filled area was slightly higher in Group 1 at both levels of observation. Despite different tapers, all the three types of cones provided a good sealing capacity in the last apical millimeter of the root canal, with good gutta-percha-sealer ratio and few or no voids.
authors.affiliation: Department of Restorative Dentistry and Endodontics, Faculty of Dental Medicine, Victor Babes University of Medicine and Pharmacy, Bd. Revolutiei no.9, 300 070, Timisoara, Romania. nical78@yahoo.com
authors.forename: Luminita Maria
authors.initials: LM
authors.lastname: Nica
authors.forename: Andreea
authors.initials: A
authors.lastname: Didilescu
authors.forename: Darian
authors.initials: D
authors.lastname: Rusu
authors.forename: Adrian
authors.initials: A
authors.lastname: Bacila
authors.forename: Stefan-Ioan
authors.initials: SI
authors.lastname: Stratul
mesh_terms: D000704:Analysis of Variance; D001840:Dental Bonding; D003763:Dental Leakage / Q000517:prevention & control*; D004853:Epoxy Resins; D006171:Gutta-Percha; D006801:Humans; D007180:Incisor; D023861:Photography, Dental; D010784:Photomicrography; D012387:Root Canal Filling Materials; D012389:Root Canal Obturation; D018709:Statistics, Nonparametric
chemical_list: D004853:Epoxy Resins; D012387:Root Canal Filling Materials; C534916:epoxy resin-based root canal sealer; D006171:Gutta-Percha