title: In vitro assessment of mandibular single/two implant-retained overdentures using stress-breaking attachments.
abstract: OBJECTIVE
  This study investigated the strain surround implants and the pressure distribution of the alveolar ridge related to implant overdentures with stress-breaking ball (SBB) attachments.
  
  
  METHODS
  Simulation models of edentulous mandibles were embedded with 1 and 2 implants to simulate a single implant-retained overdenture (S-IOD) and a two-implant-retained overdenture (T-IOD), respectively. The implants were connected to the denture base with the following conditions: complete separation between the denture base and implant with cover screws as a conventional complete denture (CD), 3 types of settlements with an SBB attachment between them, and a conventional ball attachment (BALL). Strain surround the implant, pressure at 5 different soft tissue areas, and displacement of the denture base were measured with loading up to 50 N.
  
  
  RESULTS
  In S-IOD and T-IOD, the strain of each SBB attachment was less than the strain shown by the BALL. The pressure at each region of the SBB attachment was less than the pressure shown with the CD and BALL.
  
  
  CONCLUSIONS
  SBB attachments prevented strain surround the implants in loading and provided optimal stress distribution.
authors.affiliation: *Graduate Student, Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan. †Clinical Professor, Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan. ‡Associate Professor, Division of Oral and Maxillofacial Implantology, Tsurumi University School of Dental Medicine, Yokohama, Japan. §Professor, Department of Removable Prosthodontics, Tsurumi University School of Dental Medicine, Yokohama, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Kono
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kurihara
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Suzuki
authors.forename: Chikahiro
authors.initials: C
authors.lastname: Ohkubo
mesh_terms: D015921:Dental Implants; D003799:Dental Stress Analysis; D003828:Denture, Overlay; D006801:Humans; D066298:In Vitro Techniques
chemical_list: D015921:Dental Implants