title: Effect of post space preparation on apical seal: influence of time interval and sealer.
abstract: OBJECTIVE
  To assess the efficacy of two sealants to preserve the apical seal after root canal preparation and cementation of posts at 24 h or 72 h after endodontic treatment.
  
  
  METHODS
  Sixty human single-root teeth were instrumented and obturated using lateral compaction technique with EndoFill [30] or AH-Plus) [30] and were prepared in one of three ways, leaving a 3 mm gutta percha remnant in all cases: without cast post preparation, with preparation after 24 h or after 72 h. After cementing the posts, the specimens were thermal cycled at 5 and 55 degrees C in water baths, submerged in 2% methylene blue dye for 72 h, embedded in acrylic resin and cut transversally into three 1-mm apical sections. Dye leakage was quantitatively assessed as the percentage leaked area.
  
  
  CONCLUSIONS
  Comparison of the apical sections showed significant differences in leakage with both sealers among the three preparation groups (p<0.001). No significant differences between sealers were found in any preparation group or in the same sections.
authors.affiliation: Department of Endodontics, School of Dentistry, University Federal de Pelotas, Rio Grande do Sul, Brazil.
authors.forename: Ana Lucia
authors.initials: AL
authors.lastname: Corrêa Pesce
authors.forename: Santiago
authors.initials: S
authors.lastname: González López
authors.forename: María Paloma
authors.initials: MP
authors.lastname: González Rodríguez
mesh_terms: D004853:Epoxy Resins; D006801:Humans; D066298:In Vitro Techniques; D012387:Root Canal Filling Materials; D018915:Root Canal Preparation; D013997:Time Factors
chemical_list: D004853:Epoxy Resins; D012387:Root Canal Filling Materials; C534916:epoxy resin-based root canal sealer; C074417:Endo-Fill