title: Influence of apical enlargement in cleaning of curved canals using negative pressure system.
abstract: This study aimed to evaluate, by scanning electron microscopy (SEM), the cleaning of canal walls with moderate curvature subjected to biomechanical preparation with different final diameters using apical negative pressure irrigation. Thirty-two mesiobuccal roots of molars were divided into 4 groups (n=8) according to the instrument's final diameter: GI: 30.02, GII: 35.02, GIII: 40.02 and GIV: 45.02. Irrigating procedure was performed at each change of instrument with 1% NaOCl using the Endovac system. Final irrigation was conducted with 17% EDTA for 5 min. The SEM photomicrographs were evaluated under 35× and 1000× magnification, by three calibrated examiners, in a double-blind design. Data were submitted to Kruskal-Wallis and Dunn's post hoc tests (α=0.05). Canals instrumented with 30.02 and 35.02 final diameters showed more debris, statistically different from the other groups (p<0.05). Comparing each root canal third, for the cervical and apical portions no statistically significant difference (p>0.05) was found among the four groups. Regarding the presence of smear layer, canals with 30.02 final diameter showed the highest scores, statistically different from the 45.02 group (p<0.05) and similar to the 35.02 and the 40.02 groups (p>0.05). Although none of the studied diameters completely removed debris and smear layer, it may be concluded that instrumentation with higher final diameters was more effective in cleaning the root canals with moderate curvature.
authors.affiliation: Dental School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Karina Torales
authors.initials: KT
authors.lastname: Lorencetti
authors.affiliation: Dental School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Yara Teresinha Corrêa
authors.initials: YT
authors.lastname: Silva-Sousa
authors.affiliation: Dental School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Gabriel Elias do
authors.initials: GE
authors.lastname: Nascimento
authors.affiliation: Dental School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Danielle Cristine Furtado
authors.initials: DC
authors.lastname: Messias
authors.affiliation: Dental School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Vivian
authors.initials: V
authors.lastname: Colucci
authors.affiliation: Dental School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Fuad
authors.initials: F
authors.lastname: Abi Rached-Junior
authors.affiliation: Dental School, University of Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Silvio Rocha Corrêa
authors.initials: SR
authors.lastname: Silva
mesh_terms: D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D004311:Double-Blind Method; D004492:Edetic Acid / Q000008:administration & dosage; D006801:Humans; D008855:Microscopy, Electron, Scanning; D011312:Pressure; D012388:Root Canal Irrigants / Q000008:administration & dosage; D018915:Root Canal Preparation / Q000295:instrumentation / Q000379:methods*; D016369:Smear Layer / Q000648:ultrastructure*; D012973:Sodium Hypochlorite / Q000008:administration & dosage; D007507:Therapeutic Irrigation / Q000295:instrumentation / Q000379:methods*; D019227:Tooth Apex / Q000648:ultrastructure*; D019237:Tooth Cervix / Q000648:ultrastructure; D014618:Vacuum
chemical_list: D012388:Root Canal Irrigants; D004492:Edetic Acid; D012973:Sodium Hypochlorite