title: Bond strength of fiber-reinforced posts to deproteinized root canal dentin.
abstract: OBJECTIVE
  This study evaluated the push-out bond strength of cemented fiber posts after deproteinization of root canal dentin walls with NaOCl. The effect of the application of an antioxidant solution (sodium ascorbate) was also evaluated.
  
  
  METHODS
  A three-step etch-and-rinse (Scotch-bond - 3M Espe) and a one-step self-etching adhesive (Xeno III - Dentsply Caulk) were evaluated. Thirty bovine incisor roots were divided into 3 groups: a. Irrigation with physiologic solution (control). b. Deproteinization with 10 minutes irrigation of 5% NaOCl. c. Deproteinization with NaOCl followed by 10 minutes irrigation with 10% ascorbic acid. Fiber posts were cemented with a dual-cured cement (Rely X ARC - 3M ESPE). The push-out bond strength was evaluated after 24 hours of storage in distilled water. The data were analyzed with three-way ANOVA, one-way ANOVA and Tukey's test (α = 0.05).
  
  
  RESULTS
  There were significant differences between groups (p < 0.05). The bond strength of Scotchbond was not influenced by the deproteinization. Xeno III showed a decrease in bond strength when deproteinized with 5% NaOCl (p < 0.05). For Xeno III, the subsequent irrigation with ascorbic acid was able to reverse the effect of the deproteinization. Considering the radicular thirds, the bond strength varied in the sequence-apical < middle < coronal.
  
  
  CONCLUSIONS
  Only the all-in-one adhesive was influenced by the deproteinization. Considering the respective control groups, both systems showed similar bond strength results.
  
  
  CONCLUSIONS
  The decreased bond strength of the self-etching adhesive following deproteinization seams to be related to the oxidant effect of the NaOCl solution and the subsequent irrigation with ascorbic acid was able to reverse the effect of the deproteinization.
authors.affiliation: Assistant Professor, Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of Sao Paulo Bauru, Sao Paulo, Brazil, e-mail: furuse@usp.br.
authors.forename: Adilson Yoshio
authors.initials: AY
authors.lastname: Furuse
authors.affiliation: Private Practice, Graduate Program in Dentistry, Positivo University, Curitiba Parana, Brazil.
authors.forename: Leonardo Fernandes
authors.initials: LF
authors.lastname: Cunha
authors.affiliation: Professor, Graduate Program in Dentistry, Positivo University, Curitiba Parana, Brazil.
authors.forename: Samantha Pugsley
authors.initials: SP
authors.lastname: Baratto
authors.affiliation: Professor, Graduate Program in Dentistry, Positivo University, Curitiba Parana, Brazil.
authors.forename: Denise Piotto
authors.initials: DP
authors.lastname: Leonardi
authors.affiliation: Professor, Graduate Program in Dentistry, Positivo University, Curitiba Parana, Brazil.
authors.forename: Gisele Aihara
authors.initials: GA
authors.lastname: Haragushiku
authors.affiliation: Professor, Graduate Program in Dentistry, Positivo University, Curitiba Parana, Brazil.
authors.forename: Carla Castiglia
authors.initials: CC
authors.lastname: Gonzaga
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry; D001205:Ascorbic Acid / Q000737:chemistry; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002417:Cattle; D002484:Cementation / Q000379:methods; D001840:Dental Bonding; D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D003799:Dental Stress Analysis / Q000295:instrumentation; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D008422:Materials Testing; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011176:Post and Core Technique / Q000295:instrumentation*; D019279:Resin Cements / Q000737:chemistry*; D012388:Root Canal Irrigants / Q000737:chemistry; D018915:Root Canal Preparation / Q000379:methods; D012973:Sodium Hypochlorite / Q000737:chemistry; D013314:Stress, Mechanical; D013997:Time Factors; D019227:Tooth Apex / Q000648:ultrastructure; D014867:Water / Q000737:chemistry
chemical_list: D000975:Antioxidants; D017220:Dentin-Bonding Agents; D011109:Polymethacrylic Acids; C462240:RelyX ARC; D019279:Resin Cements; D012388:Root Canal Irrigants; C084018:Scotchbond Multi-Purpose; C487957:Xeno III; D014867:Water; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate; D012973:Sodium Hypochlorite; D001205:Ascorbic Acid