title: Post removal using a thick-walled hollow tube post design.
abstract: OBJECTIVE
  The retention of a post into the root is critical for the successful restoration of an endodontically treated tooth. A total of 80 Access Posts (Nos. 0, 1, 2, and 3) comprising eight groups were cemented in root canals with two different luting agents, Flexi-Flow cem with titanium and zinc phosphate cement.
  
  
  METHODS
  Removal of these Access Posts was then performed with the corresponding retreatment drills.
  
  
  RESULTS
  None of the samples for the No. 0 Access Posts were removed by extraction with the retreatment drills. None of the samples for the No. 1 Access Posts cemented with zinc phosphate were removed by extraction with the retreatment drills. All these posts were removed by hand with a hemostat, after breakage of the cement seal. 60% (group 3) and 40% (group 7) of the samples for the No. 2 Access Posts were removed by extraction with the corresponding retreatment drills. 80% (group 4) and 70% (group 8) of samples for the No. 3 Access Posts were removed by extraction with the corresponding retreatment drills. On an average removal of each Access Post Nos. 0 and 1 took between 1 and 2 minutes. On an average removal of each Access Post (Nos. 2 and 3) took between 2 and 3 minutes.
  
  
  CONCLUSIONS
  No root fractures were observed for any sample with either technique. This was confirmed by visual and radiographic analysis.
authors.affiliation: Essential Dental Laboratories, S. Hackensack, New Jersey, USA.
authors.forename: B I
authors.initials: BI
authors.lastname: Cohen
authors.forename: M
authors.initials: M
authors.lastname: Pagnillo
authors.forename: S
authors.initials: S
authors.lastname: Condos
authors.forename: B L
authors.initials: BL
authors.lastname: Musikant
authors.forename: A S
authors.initials: AS
authors.lastname: Deutsch
mesh_terms: D003188:Composite Resins; D003738:Dental Cements; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D006801:Humans; D008422:Materials Testing; D011176:Post and Core Technique; D011475:Prosthesis Failure; D012086:Reoperation; D018915:Root Canal Preparation / Q000295:instrumentation; D013314:Stress, Mechanical; D013718:Tensile Strength; D014025:Titanium; D015036:Zinc Phosphate Cement
chemical_list: D003188:Composite Resins; D003738:Dental Cements; C101035:Flexi-Flow cement; D015036:Zinc Phosphate Cement; D014025:Titanium