title: Effect of smear layer removal on the diffusion permeability of human roots.
abstract: Ten human maxillary incisors, extracted because of periodontal disease or nonrestorable caries, were obtained and instrumented to a size #70 K-Flex file at the working length using a standard stepback technique. Tritiated water (3H2O) was placed in the root canals and allowed to diffuse to the external surface of the roots until it reached a constant rate. The smear layer in each of the experimental roots was then removed using 0.5 M EDTA followed by 5.25% sodium hypochlorite (NaOCI). The constant rate diffusion of 3H2O was remeasured. The roots were then stored in deionized H2O for 2 months and the constant rate diffusion of 3H2O was remeasured. A statistically significant difference was noted between all three groups. A decrease in the diffusion permeability of the root to 3H2O was noted immediately after smear layer removal and the highest permeability was recorded after storage in the deionized water for 2 months.
authors.affiliation: U.S. Army Dental Activity, Ft. Leonard Wood, MO.
authors.forename: D A
authors.initials: DA
authors.lastname: Galvan
authors.forename: A E
authors.initials: AE
authors.lastname: Ciarlone
authors.forename: D H
authors.initials: DH
authors.lastname: Pashley
authors.forename: J C
authors.initials: JC
authors.lastname: Kulild
authors.forename: P D
authors.initials: PD
authors.lastname: Primack
authors.forename: M D
authors.initials: MD
authors.lastname: Simpson
mesh_terms: D003804:Dentin / Q000502:physiology; D003806:Dentin Permeability; D004058:Diffusion; D006801:Humans; D016369:Smear Layer; D014092:Tooth Root / Q000502:physiology*; D014867:Water
chemical_list: D014867:Water