title: Effect of disinfection solutions on the adhesion force of root canal filling materials.
abstract: BACKGROUND
  Sodium hypochlorite (NaOCl) and chlorhexidine (CHX) are usually used to disinfect gutta-percha (GP) and Resilon (Res) cones. This study investigated the adhesion force (Fad) between root canal sealers and GP and Res cones following different disinfection protocols by using atomic force microscopy.
  
  
  METHODS
  Nine flat surfaces of each material were obtained with medium points of GP and Res. The samples were divided into 6 groups (n = 3): control group GP, immersion in distilled water (DW); NaOCl group GP, immersion in 5.25% NaOCl and then washing with DW; CHX group GP, immersion in 2% CHX and then washing with DW; control group Res, immersion in DW; NaOCl group Res, immersion in 5.25% NaOCl and then washing with DW; and CHX group Res, immersion in 2% CHX and then washing with DW. Atomic force microscopy tips containing AH Plus sealer were used to obtain force versus distance curves regarding GP surfaces. Fad was calculated from the force curves. The same procedure was performed with Real Seal SE and Res surfaces. Data were statistically analyzed.
  
  
  RESULTS
  A higher Fad between solid filling materials (GP and Res) and root canal sealers was found when CHX solution was used. Treatment with NaOCl solution did not show influence on the Fad values.
  
  
  CONCLUSIONS
  The decontamination of GP and Res with 2% CHX resulted in higher Fad values. The use of CHX in the disinfection process of GP and Res cones might be a better option before root canal obturation.
authors.affiliation: Department of Metallurgic and Materials Engineering, Federal University of Rio de Janeiro, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Danielle Ferreira
authors.initials: DF
authors.lastname: de Assis
authors.forename: Maíra
authors.initials: M
authors.lastname: do Prado
authors.forename: Renata A
authors.initials: RA
authors.lastname: Simão
mesh_terms: D000268:Adhesiveness; D002710:Chlorhexidine; D003188:Composite Resins; D001840:Dental Bonding; D019551:Dental Disinfectants; D003799:Dental Stress Analysis; D004853:Epoxy Resins; D006171:Gutta-Percha; D006801:Humans; D008422:Materials Testing; D018625:Microscopy, Atomic Force; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D012973:Sodium Hypochlorite; D012996:Solutions
chemical_list: D003188:Composite Resins; D019551:Dental Disinfectants; D004853:Epoxy Resins; C511498:Real Seal composite resin; D012387:Root Canal Filling Materials; D012388:Root Canal Irrigants; D012996:Solutions; C534916:epoxy resin-based root canal sealer; C486892:resilon sealer; D006171:Gutta-Percha; D012973:Sodium Hypochlorite; D002710:Chlorhexidine