title: The influence of smear layer in lateral channels filling.
abstract: This in vitro study evaluated the ability of a warm gutta-percha obturation system Thermafil to fill lateral channels in presence/absence of smear layer. Forty single-rooted extracted human teeth were randomly divided into two groups for which different irrigation regimens were used: group A, 5 ml of 5% NaOCl + 2.5 ml of 3.6% H(2)O(2); group B, 5 ml of 5% NaOCl 5% + 2.5 ml of 17% ethylenediamine tetraacetic acid. A conventional crown-down preparation technique was employed. Obturation was performed using epoxy resin-based cement (AH Plus) and a warm gutta-percha plastic carrier system (Thermafil). Specimens were cleared in methyl salicylate and analyzed under a stereomicroscope to evaluate the number, length, and diameter of lateral channels. Lateral channels were identified in both groups at medium and apical thirds. Additional samples were prepared for scanning electron microscopy inspection to confirm the presence of smear layer in group A, and the absence of smear layer in group B. All lateral channels resulted filled in both groups. No statistically significant differences regarding number, length, and diameter were observed between the two groups. Smear layer did not prevent the sealing of lateral channels.
authors.affiliation: Endodontics Unit, Department of Oral Sciences, University of Bologna, via San Vitale 59, 40125 Bologna, Italy. angelica.bertacci2@unibo.it
authors.forename: Angelica
authors.initials: A
authors.lastname: Bertacci
authors.forename: Chiara
authors.initials: C
authors.lastname: Baroni
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Breschi
authors.forename: Mauro
authors.initials: M
authors.lastname: Venturi
authors.forename: Carlo
authors.initials: C
authors.lastname: Prati
mesh_terms: D002614:Chelating Agents / Q000627:therapeutic use; D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D004492:Edetic Acid / Q000627:therapeutic use; D004853:Epoxy Resins / Q000627:therapeutic use; D006171:Gutta-Percha / Q000627:therapeutic use*; D006801:Humans; D006861:Hydrogen Peroxide / Q000627:therapeutic use; D008422:Materials Testing; D008855:Microscopy, Electron, Scanning; D016877:Oxidants / Q000627:therapeutic use; D012387:Root Canal Filling Materials / Q000627:therapeutic use*; D012388:Root Canal Irrigants / Q000627:therapeutic use; D012389:Root Canal Obturation / Q000379:methods*; D018915:Root Canal Preparation / Q000379:methods; D016369:Smear Layer; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D013499:Surface Properties; D019227:Tooth Apex / Q000648:ultrastructure
chemical_list: D002614:Chelating Agents; D004853:Epoxy Resins; D016877:Oxidants; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; C534916:epoxy resin-based root canal sealer; D006171:Gutta-Percha; D004492:Edetic Acid; D006861:Hydrogen Peroxide; D012973:Sodium Hypochlorite