title: Comparison of the retentive properties of six prefabricated post overdenture attachment systems.
abstract: BACKGROUND
  There are few research studies concerning prefabricated posts overdenture attachment systems using multiple pull cycles.
  
  
  OBJECTIVE
  This study tested 6 prefabricated post overdenture attachment systems (AccessPost Overdenture, ERA white and ERA grey, Flexi-Overdenture, O-SO and ZAAG) measured to simulate wear over a 2000 pull cycle and compared the in vitro retention, measured (pounds).
  
  
  METHODS
  Records of the pounds of force necessary to separate each system were made at the beginning of testing, at pull 10 and then at every 50th pull until the 2000th pull was attained. All pulls were performed manually with a Shimpo force gauge. Absolute force (AF) and relative force (RF) were compared, AF being the force required at any pull to separate the overdenture device, whereas RF is the force required at the first pull.
  
  
  RESULTS
  There was considerable difference of the force required at pull 1 for the ERA white, O-SO and ZAAG anchor systems, then the AccessPost overdenture, and finally the Flexi-Overdenture and ERA grey attachment systems.
  
  
  CONCLUSIONS
  At pull 2000, there was no statistical difference between any of the attachments studied. The amount of force necessary to offer functional retention to a specific patient wearing an overdenture may vary considerably, depending on the many factors in fabricating the overdenture, and the age, strength, musculature, and the expectations of the patient.
authors.affiliation: Columbia University School of Dental and Oral Surgery, New York, NY, USA. DANNYDDS@aol.com
authors.forename: D D
authors.initials: DD
authors.lastname: Epstein
authors.forename: P L
authors.initials: PL
authors.lastname: Epstein
authors.forename: B I
authors.initials: BI
authors.lastname: Cohen
authors.forename: M K
authors.initials: MK
authors.lastname: Pagnillo
mesh_terms: D017268:Dental Prosthesis Retention / Q000295:instrumentation* / Q000379:methods / Q000706:statistics & numerical data; D003799:Dental Stress Analysis / Q000379:methods / Q000706:statistics & numerical data; D003828:Denture, Overlay / Q000706:statistics & numerical data; D006801:Humans; D066298:In Vitro Techniques; D011176:Post and Core Technique / Q000295:instrumentation* / Q000706:statistics & numerical data; D013997:Time Factors