title: Influence of filling materials on the bonding interface of thin-walled roots reinforced with resin and quartz fiber posts.
abstract: BACKGROUND
  A common complication during the restoration of severely destroyed teeth is the loss of coronal root dentine. The aim of this study was to evaluate the influence of different sealers on the bonding interface of weakened roots reinforced with resin and fiber posts.
  
  
  METHODS
  Sixty extracted maxillary canines were used. The crowns were removed, and the thickness of root dentine was reduced in the experimental (n = 40) and positive control (n = 10) groups. The specimens of experimental group were assigned to four subgroups (n = 10) according to the filling material: gutta-percha + Grossmann's sealer, gutta-percha + AH Plus (Dentsply De Trey Gmbh, Konstanz, Germany), gutta-percha + Epiphany (Pentron Clinical Technologies, Wallingford, CT), and Resilon (Resilon Research LLC, Madison, CT) + Epiphany. In the negative control group (n = 10), canals were not filled. After post space preparation, the roots were restored with composite resin light-activated through a translucent fiber post. After 24 hours, specimens were transversally sectioned into 1-mm-thick slices. Push-out test and scanning electron microscopic (SEM) analyses of different regions were performed. Data from push-out test were analyzed by using Tukey post hoc multiple comparison tests. The percentage of failure type was calculated. Data from SEM analysis were compared by Friedman and Kruskal-Wallis tests (α = 0.05).
  
  
  RESULTS
  The mean bond strength was significantly higher in the negative control group as compared with the other groups (P < .05). In all groups, the most frequent type of failure was adhesive. Overall, apical and middle regions presented a lower density of resin tags than the coronal region (P < .05).
  
  
  CONCLUSIONS
  The push-out bond strength was not affected by sealer or region. The canal region affected significantly the resin tag morphology and density at the bonding interface.
authors.affiliation: Department of Restorative Dentistry, Faculty of Dentistry, University of São Paulo, Ribeirão Preto, São Paulo, Brazil.
authors.forename: Cid Alonso
authors.initials: CA
authors.lastname: Manicardi
authors.forename: Marco Aurélio
authors.initials: MA
authors.lastname: Versiani
authors.forename: Paulo César
authors.initials: PC
authors.lastname: Saquy
authors.forename: Jesus Djalma
authors.initials: JD
authors.lastname: Pécora
authors.forename: Manoel Damião
authors.initials: MD
authors.lastname: de Sousa-Neto
mesh_terms: D000268:Adhesiveness; D003188:Composite Resins / Q000737:chemistry*; D001840:Dental Bonding; D003764:Dental Materials / Q000737:chemistry*; D017267:Dental Prosthesis Design; D003786:Dental Pulp Cavity / Q000648:ultrastructure*; D003799:Dental Stress Analysis / Q000295:instrumentation; D003804:Dentin / Q000648:ultrastructure*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D004853:Epoxy Resins / Q000737:chemistry; D006171:Gutta-Percha / Q000737:chemistry; D006801:Humans; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D011176:Post and Core Technique / Q000295:instrumentation*; D011791:Quartz / Q000737:chemistry*; D012387:Root Canal Filling Materials / Q000737:chemistry*; D018915:Root Canal Preparation / Q000379:methods; D013314:Stress, Mechanical; D013499:Surface Properties; D013997:Time Factors; D019227:Tooth Apex / Q000648:ultrastructure; D015035:Zinc Oxide-Eugenol Cement / Q000737:chemistry
chemical_list: D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D004853:Epoxy Resins; D008689:Methacrylates; D012387:Root Canal Filling Materials; D015035:Zinc Oxide-Eugenol Cement; C486893:epiphany sealer; C534916:epoxy resin-based root canal sealer; C486892:resilon sealer; C045432:Grossman's sealer; D011791:Quartz; C100742:All-Bond 2; D006171:Gutta-Percha