title: Residues of different gel formulations on dentinal walls: A SEM/EDS analysis.
abstract: The aim of this study was to evaluate the presence of residues of sodium hypochlorite gel, chlorhexidine gel, and EDTA gel on dentinal walls after canal preparation through chemical SEM- elemental chemical microanalysis (EDS) analysis. Forty-eight single-rooted teeth were selected. They had their crowns sectioned and were instrumented with a reciprocating system. The canals were irrigated with 5 mL of saline solution during root canal preparation. After instrumentation, the root canals were irrigated with 3 mL 17% EDTA followed by 1 min of ultrasonic passive activation (3× 20 sec) to remove the smear layer, and then irrigated with 3 mL of saline solution. The specimens were randomized into three groups (n = 12) according to the chemical substance that filled the root canal for 30 min: GI: 5.5% sodium hypochlorite gel; GII: 2% chlorhexidine gel; GIII: 24% EDTA gel; Negative control group: no substance was used. Then, the root canals were irrigated with 6 mL of saline solution followed by 1 min of ultrasonic passive activation (3× 20 sec). After ultrasonic activation, the canals were irrigated with 2 mL saline. The roots were sectioned, and the percentage of each chemical element present in the samples was analyzed through chemical SEM-EDS microanalysis. All experimental groups showed a significantly higher percentage of chemical elements (Na and/or Cl) than the control group (P < 0.03). This in vitro study has shown that, regardless of chemical solutions used even after the final irrigation protocol, chemical residues of different substances remained attached to the root canal walls.
authors: Department of Conservative Dentistry, Federal University of Rio Grande Do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors: Angela Longo
authors: AL
authors: do Nascimento
authors: Department of Conservative Dentistry, Federal University of Rio Grande Do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors: Fernanda Hoffmann
authors: FH
authors: Busanello
authors: Department of Conservative Dentistry, Federal University of Rio Grande Do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors: Marcus Vinícius Reis
authors: MV
authors: Só
authors: Department of Restorative Dentistry, School of Dentistry, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil.
authors: Milton Carlos
authors: MC
authors: Kuga
authors: Department of Prosthodontics, Dental School, University of Southern Santa Catarina, Tubarão, Santa Catarina, Brazil.
authors: Jefferson Ricardo
authors: JR
authors: Pereira
authors: Department of Conservative Dentistry, Federal University of Rio Grande Do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors: Fabiana Soares
authors: FS
authors: Grecca
mesh_terms: D002710:Chlorhexidine / Q000032:analysis*; D003804:Dentin / Q000737:chemistry*; D004492:Edetic Acid / Q000032:analysis*; D004577:Electron Probe Microanalysis; D005782:Gels; D008855:Microscopy, Electron, Scanning; D018915:Root Canal Preparation; D012973:Sodium Hypochlorite / Q000032:analysis*
chemical_list: D005782:Gels; D004492:Edetic Acid; D012973:Sodium Hypochlorite; D002710:Chlorhexidine
keywords: EDTA; chlorhexidine; electron probe microanalysis; endodontics; sodium hypochlorite