title: Pullout bond strength of fiber posts luted to different depths and submitted to artificial aging.
abstract: BACKGROUND
  The extension of fiber post cementation often does not seem to influence the fracture resistance of restorations. This study evaluated the effects of cementation depths on the retention of fiber posts submitted to artificial aging.
  
  
  METHODS
  One hundred and sixty bovine incisors were selected to assess post retention. Following endodontic treatment, the canals were flared with diamonds burs. Postholes were prepared in lengths of 5 or 10 mm, after which fiber posts were relined with composite resin and luted with RelyX ARC or RelyX Unicem. The samples were then submitted to thermal and/or mechanical cycling before testing their pullout bond strengths. Absence of cycling was used as a control. The results of each cement were submitted to two-way and post hoc Tukey tests (α=0.05).
  
  
  RESULTS
  Independent of the aging protocol, a depth of 10 mm showed higher pullout bond strength than did 5 mm, except for RelyX Unicem without cycling. For RelyX ARC, thermomechanical cycling resulted in lower values than in the absence of cycling. Mechanical cycling alone promoted the highest bond strength when the posts were luted with RelyX Unicem.
  
  
  CONCLUSIONS
  The effect of artificial aging on the pullout bond strength is dependent on the type of material and the depth.
authors: V C
authors: VC
authors: Macedo
authors: N A Y
authors: NA
authors: Souza
authors: A L
authors: AL
authors: Faria e Silva
authors: C
authors: C
authors: Cotes
authors: C
authors: C
authors: da Silva
authors: M
authors: M
authors: Martinelli
authors: E T
authors: ET
authors: Kimpara
mesh_terms: D000818:Animals; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D002417:Cattle; D002484:Cementation / Q000379:methods; D003188:Composite Resins / Q000737:chemistry; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry; D003764:Dental Materials / Q000737:chemistry; D017268:Dental Prosthesis Retention; D003799:Dental Stress Analysis / Q000295:instrumentation; D004853:Epoxy Resins / Q000737:chemistry; D005898:Glass / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D011176:Post and Core Technique / Q000295:instrumentation*; D019279:Resin Cements / Q000737:chemistry*; D018915:Root Canal Preparation / Q000379:methods; D012821:Silanes / Q000737:chemistry; D013314:Stress, Mechanical; D013499:Surface Properties; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry
chemical_list: C554641:Adper single bond 2; D003188:Composite Resins; D003738:Dental Cements; D003764:Dental Materials; D004853:Epoxy Resins; C444701:Filtek Z250; D011109:Polymethacrylic Acids; C483701:Rely X Unicem; C462240:RelyX ARC; D019279:Resin Cements; D012821:Silanes; C009753:fiberglass; D014867:Water; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate