title: Comparative in vitro study of apically extruded material after four different root canal Instrumentation techniques.
abstract: Forty newly extracted human upper central incisors were submitted to root canal instrumentation 1 mm from the apex using four different techniques: standard, step-preparation, crown-down, and ultrasound, with distilled and deionized water as the irrigating solution. The extrusion product was collected into a collecting device constructed for this purpose. Extrusion was calculated by the determination of the mass of extruded material. The step-preparation technique caused a larger amount of extrusion than the standard technique, which in turn caused greater extrusion than the crown-down and ultrasound techniques. All techniques used caused extrusion of material beyond the apical foramen.
authors.affiliation: Disciplina de Endodontia, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Brasil.
authors.forename: L P
authors.initials: LP
authors.lastname: Vansan
authors.forename: J D
authors.initials: JD
authors.lastname: Pécora
authors.forename: W F
authors.initials: WF
authors.lastname: da Costa
authors.forename: R G
authors.initials: RG
authors.lastname: Silva
authors.forename: R N
authors.initials: RN
authors.lastname: Savioli
mesh_terms: D003763:Dental Leakage / Q000209:etiology / Q000378:metabolism*; D003764:Dental Materials / Q000493:pharmacokinetics*; D006801:Humans; D066298:In Vitro Techniques; D007180:Incisor / Q000378:metabolism; D008437:Maxilla; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D019227:Tooth Apex / Q000378:metabolism*
chemical_list: D003764:Dental Materials