title: Retention and Stability of Implant-Retained Mandibular Overdentures Using Different Types of Resilient Attachments: An In Vitro Study.
abstract: OBJECTIVE
  The aim of this study was to evaluate and compare the retention and stability of mandibular implant overdentures using different types of resilient attachments.
  
  
  METHODS
  Two implant analogs were inserted in the canine areas of an acrylic edentulous mandibular model. A metal-reinforced experimental overdenture was constructed and connected to the implant analogs (on two occasions) using either resilient telescopic or Locator attachments. Locators were divided into three subgroups according to the degree of retention of the male nylon insert: Locator extra-light retention (blue insert), Locator light retention (pink insert), and Locator medium retention (transparent insert). Vertical and oblique (anterior, posterior, and lateral) dislodging forces were measured at the beginning of the study (initial retention) and after 540 cycles of denture insertion and removal (final retention).
  
  
  RESULTS
  For all dislodging forces, Locator medium recorded the highest initial and final retention. Telescopic attachments recorded the lowest retention during vertical and anterior dislodging, and Locator extra-light recorded the lowest retention during lateral and posterior dislodging. For all types of Locator attachments, anterior dislodging recorded the highest initial and final retention, and lateral dislodging recorded the lowest retention. For the telescopic attachment, posterior dislodgment recorded the highest initial and final retention, and anterior dislodging recorded the lowest retention.
  
  
  CONCLUSIONS
  After repeated denture insertions and removals, the highest retention and stability were recorded with Locator medium followed by Locator light. The lowest retention was recorded with resilient telescopic attachment, and the lowest stability was recorded with Locator extra-light.
authors.forename: Moustafa Abdou
authors.initials: MA
authors.lastname: ELsyad
authors.forename: Nora Nory
authors.initials: NN
authors.lastname: Agha
authors.forename: Ahmed Ali
authors.initials: AA
authors.lastname: Habib
mesh_terms: D000180:Acrylic Resins; D000704:Analysis of Variance; D003758:Dental Implantation, Endosseous / Q000379:methods*; D003764:Dental Materials; D019094:Dental Prosthesis, Implant-Supported / Q000295:instrumentation*; D003799:Dental Stress Analysis; D003779:Denture Design; D003781:Denture Retention / Q000592:standards*; D003828:Denture, Overlay / Q000592:standards*; D006801:Humans; D008334:Mandible / Q000601:surgery; D008954:Models, Biological; D009066:Mouth, Edentulous / Q000601:surgery; D013314:Stress, Mechanical
chemical_list: D000180:Acrylic Resins; D003764:Dental Materials