title: Effects of various irrigation/aspiration protocols on cleaning of flattened root canals.
abstract: This study aimed to evaluate, by means of scanning electron microscopy (SEM), the cleaning of flattened root canals, varying irrigation/aspiration protocols during biomechanical preparation. Thirdy human mandibular incisors were distributed into three groups (n = 10) according to the aspiration/irrigation protocols: conventional, conventional + brush, and apical negative pressure irrigation. Irrigation procedure was performed with 5 mL of 1% NaOCl at each change of instrument; final irrigation was conducted with 17% EDTA for 5 min. After biomechanical preparation, the roots were sectioned and prepared for SEM analysis. The images obtained were evaluated under 35× and 1,000× magnification by three calibrated examiners, following a double-blind design. All data were analyzed using Kruskal-Wallis and Dunn's post hoc tests (α = 0.05). Canals wherein the conventional method and apical negative pressure irrigation were employed revealed less debris, statistically different from the conventional + brush group (p < 0.05). Regarding the presence of smears, apical negative pressure irrigation was more effective in cleaning, showing lowest scores (p < 0.05), compared with the other tested protocols. Comparing each root canal third revealed that the apical portion was difficult to clean as all the tested protocols showed similar high scores (p > 0.05), both for the presence of debris and smear layer. In conclusion, although none of the studied irrigation/aspiration protocols have completely cleaned flattened root canals, apical negative pressure irrigation was more effective in smear layer removal, whereas the conventional + brush protocol was the least effective in removing the debris and smear layer.
authors.affiliation: Department of Dentistry, School of Dentistry, Universidade de Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Diego Henrique da Silva
authors.initials: DH
authors.lastname: Mendonça
authors.affiliation: Department of Dentistry, School of Dentistry, Universidade de Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Vivian
authors.initials: V
authors.lastname: Colucci
authors.affiliation: Department of Dentistry, School of Dentistry, Universidade de Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Fuad Jacob Abi
authors.initials: FJ
authors.lastname: Rached-Junior
authors.affiliation: Department of Dentistry, School of Dentistry, Universidade de Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Carlos Eduardo Saraiva
authors.initials: CE
authors.lastname: Miranda
authors.affiliation: Department of Dentistry, School of Dentistry, Universidade de Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Yara Teresinha Corrêa
authors.initials: YT
authors.lastname: Silva-Sousa
authors.affiliation: Department of Dentistry, School of Dentistry, Universidade de Ribeirão Preto, Ribeirão Preto, SP, Brazil.
authors.forename: Silvio Rocha Corrêa da
authors.initials: SR
authors.lastname: Silva
mesh_terms: D003646:Debridement / Q000295:instrumentation / Q000379:methods; D003786:Dental Pulp Cavity / Q000033:anatomy & histology / Q000187:drug effects*; D003804:Dentin / Q000187:drug effects; D004202:Disinfectants / Q000627:therapeutic use; D004492:Edetic Acid / Q000627:therapeutic use; D006801:Humans; D008855:Microscopy, Electron, Scanning; D015203:Reproducibility of Results; D012388:Root Canal Irrigants / Q000627:therapeutic use*; D018915:Root Canal Preparation / Q000295:instrumentation* / Q000379:methods*; D016369:Smear Layer / Q000628:therapy; D012973:Sodium Hypochlorite / Q000627:therapeutic use; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D004202:Disinfectants; D012388:Root Canal Irrigants; D004492:Edetic Acid; D012973:Sodium Hypochlorite