title: In situ assessment of the setting of tricalcium silicate-based sealers using a dentin pressure model.
abstract: BACKGROUND
  EndoSequence BC Sealer (Brasseler, Savannah, GA) is a premixed tricalcium silicate-based root canal sealer that requires moisture from the root dentin to hydrate. The aim of this study was to investigate the setting of EndoSequence BC Sealer and other sealers in contact with human dentin in a simulated clinical environment.
  
  
  METHODS
  EndoSequence BC Sealer, MTA Fillapex (Angelus, Londrina, Brazil), Septodont Sealer (Septodont, Saint Maur-des-Fosses, France), and Apexit Plus (Ivoclar, Schaan, Lichtenstein) were assessed. Caries-free lower premolars extracted for orthodontic purposes in patients aged 13-16 years were standardized to a 10-mm root length and were filled with test sealers and set up in a dentin pressure model for 14 days. In addition, set sealers immersed in physiologic solution for 14 days were also assessed. The set materials in solution and materials retrieved from the dentin pressure setup were characterized by scanning electron microscopy and X-ray diffraction analysis. The setting time and radiopacity were assessed using ISO 6876:2002 specifications. Furthermore, mineral ion leaching was evaluated by inductively coupled plasma mass spectrometry.
  
  
  RESULTS
  All the sealers tested exhibited formation of a calcium phosphate phase when in contact with physiologic solution. Septodont Sealer and Apexit Plus did not exhibit the formation of a calcium phosphate phase in the dentin pressure setup. The fluid in the system was enough to allow the setting of EndoSequence BC Sealer, which did not set in a dry environment. All materials leached calcium with the Septodont Sealer, exhibiting double the calcium ion leaching compared with EndoSequence BC Sealer.
  
  
  CONCLUSIONS
  Using the dentinal fluid pressure system resulted in an adequate flow of dentinal fluid that allowed EndoSequence BC Sealer to set inside the root canal. Although the sealers tested were tricalcium silicate based, the hydration reaction and bioactivity in the presence of dentinal fluid were different to hydration in vitro. Thus, clinically, material bioactivity cannot be assumed.
authors.affiliation: Faculty of Dental Surgery, Department of Restorative Dentistry, University of Malta, Msida, Malta.
authors.forename: Maria
authors.initials: M
authors.lastname: Xuereb
authors.affiliation: Faculty of Dental Surgery, Department of Restorative Dentistry, University of Malta, Msida, Malta.
authors.forename: Paul
authors.initials: P
authors.lastname: Vella
authors.affiliation: EM Douai, LGCgE-GCE, Douai, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Damidot
authors.affiliation: Faculty of Science, Department of Physics, University of Malta, Msida, Malta.
authors.forename: Charles V
authors.initials: CV
authors.lastname: Sammut
authors.affiliation: Faculty of Dental Surgery, Department of Restorative Dentistry, University of Malta, Msida, Malta. Electronic address: josette.camilleri@um.edu.mt.
authors.forename: Josette
authors.initials: J
authors.lastname: Camilleri
mesh_terms: D000293:Adolescent; D017610:Calcium Compounds / Q000737:chemistry*; D002130:Calcium Phosphates / Q000737:chemistry; D003786:Dental Pulp Cavity; D003804:Dentin / Q000737:chemistry* / Q000000981:diagnostic imaging; D006801:Humans; D008422:Materials Testing; D012387:Root Canal Filling Materials / Q000737:chemistry*; D017640:Silicates / Q000737:chemistry*; D013499:Surface Properties; D014961:X-Ray Diffraction; D015035:Zinc Oxide-Eugenol Cement / Q000737:chemistry*
chemical_list: D017610:Calcium Compounds; D002130:Calcium Phosphates; D012387:Root Canal Filling Materials; D017640:Silicates; D015035:Zinc Oxide-Eugenol Cement; C112894:canals sealer; C506393:tricalcium silicate; C020243:calcium phosphate
keywords: Apexit Plus; EndoSequence BC sealer; MTA Fillapex; Septodont Sealer; dentin pressure model; hydration; setting