title: [Effects of two endodontic sealers on the bond strength of two fiber posts].
abstract: OBJECTIVE
  To study the effects of two different endodontic sealers on the bond strength of two fiber posts cemented with adhesive resin cement.
  
  
  METHODS
  Twenty-eight crownless human maxillary central incisors were prepared with the step-back technique and randomly divided into four groups according endodontic sealer and fiber: Group A, Cortisomol sealer+Matchpost fiber post; Group B, Cortisomol sealer+Macrolock fiber post; Group C, Guttaflow sealer+Matchpost fiber post; Group D, Guttaflow sealer+Macrolock fiber post. One week after fiber posts were bonded, a thin-slice push-out test was performed in a universal machine. Morphologic structure of the root canal dentin surfaces etched and the adhesive interfaces were examined by scanning electron microscopy (SEM).
  
  
  RESULTS
  The bond strengths of 4 groups were (7.06 +/- 3.22), (9.31 +/- 3.61), (6.90 +/- 3.13), (9.71 +/- 3.42) MPa. The bond strengths of group B and D were significantly higher than that of group A and C (P < 0.05). There was no significant difference between group A and C, group B and D (P > 0.05). The cervical third had the highest mean push-out bond strength, next to middle third and apical third (P < 0.01). SEM showed that larger numbers of the dentin tubules were open after the root canals were etched and penetration of resin tags into the dentinal tubules increased in the coronal root region when compared with the apical root region.
  
  
  CONCLUSIONS
  The shear bond strength doesn't have relationship with endodontic sealers. The serration significantly increases the retention of fiber post. The bond strengths are different at the three root segment sites.
authors.affiliation: Dept. of Prosthodontics, Suzhou Stomatological Hospital, Suzhou 215005, China.
authors.forename: Guangzheng
authors.initials: G
authors.lastname: Han
authors.forename: Zhenghui
authors.initials: Z
authors.lastname: Xiong
authors.forename: Yaming
authors.initials: Y
authors.lastname: Chen
mesh_terms: D001840:Dental Bonding; D003804:Dentin; D017220:Dentin-Bonding Agents; D004129:Dimethylpolysiloxanes; D004338:Drug Combinations; D006171:Gutta-Percha; D006801:Humans; D007180:Incisor; D011176:Post and Core Technique; D019279:Resin Cements; D012390:Root Canal Therapy; D014092:Tooth Root; D015035:Zinc Oxide-Eugenol Cement
chemical_list: C495565:Cortisomol; D017220:Dentin-Bonding Agents; D004129:Dimethylpolysiloxanes; D004338:Drug Combinations; C515718:GuttaFlow; D019279:Resin Cements; D015035:Zinc Oxide-Eugenol Cement; C095998:Adhesive cement; D006171:Gutta-Percha