title: The influence of pressure changes on the retentive force and coronal microleakage of different types of posts in endodontically treated teeth during simulated dives.
abstract: OBJECTIVE
  We assessed the influence of a simulated diving environment on the interfacial microleakage and retentive forces of different post types in root-canal-filled teeth.
  
  
  METHODS
  One-hundred-and-twenty extracted, single-rooted teeth were endodontically treated and were randomly divided into three groups according to the post and cement used: ER Post/Harvard cement (Titanium), CeraPost/DentinBuild Evo (Zirconia), DT Light Post/Calibra (FRC). Each group was randomly divided into two equal subgroups, a control group, and an experimental group, subjected to simulated dives to 456 kPa in a diving chamber. For 10 specimens of each subgroup the pull-out strength and the coronal microleakage were measured.
  
  
  RESULTS
  Significant differences in the linear coronal penetration were observed between the Titanium and FRC groups (experimental group P ≤ 0.001; control group P = 0.02). Diving simulation had no significant impact on the microleakage for the three post types. The FRC groups showed significantly higher retentive strength values compared to the Titanium and Zirconia groups before and after simulated diving. The pull-out strength of the titanium experimental group was significantly less than the control group (P = 0.008).
  
  
  CONCLUSIONS
  Following root canal treatment the combination of fibre-reinforced posts and resin cement should be preferred for patients requiring retention for tooth restorations using posts that are likely to be exposed to hyperbaric conditions.
authors.affiliation: Centre for Prosthetic Dentistry and Dental Biomaterials Danube Private University, Steiner Landstraße 124 A-3500 Krems-Stein, Austria. gergo.mitov@dp-uni.ac.at.
authors.forename: Gergo
authors.initials: G
authors.lastname: Mitov
authors.affiliation: Department for Maxillofacial Surgery, Ludwig-Maximilians-Universitat Munchen, Munich, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Draenert
authors.affiliation: Department for Oral and Maxillofacial Surgery, Universitats Spital Zurich, Zurich, Switzerland.
authors.forename: Paul
authors.initials: P
authors.lastname: Schumann
authors.affiliation: Department for Oral and Maxillofacial Surgery, Medizinische Hochschule Hannover, Hannover, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Stötzer
authors.affiliation: Centre for CAD/CAM and Digital Dentistry, Danube Private University, Krems, Austria.
authors.forename: Constantin
authors.initials: C
authors.lastname: von See
mesh_terms: D000399:Air Pressure; D058868:Compressed Air; D003738:Dental Cements; D003763:Dental Leakage; D004242:Diving; D006801:Humans; D011176:Post and Core Technique; D011897:Random Allocation; D019279:Resin Cements; D012389:Root Canal Obturation; D018915:Root Canal Preparation / Q000379:methods; D014025:Titanium; D015036:Zinc Phosphate Cement; D015040:Zirconium
chemical_list: C433205:Calibra; D003738:Dental Cements; D019279:Resin Cements; D015036:Zinc Phosphate Cement; C074226:Harvard Cement; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide
keywords: Dental; barodontalgia; barotrauma; pressure