title: The effect of abutment dis/reconnections on peri-implant bone resorption: a radiologic study of platform-switched and non-platform-switched implants placed in animals.
abstract: OBJECTIVE
  The purpose of this animal study was to radiologically measure the influence of abutment disconnection on bone resorption and to compare this influence on platform-switched vs. non-platform-switched implants.
  
  
  METHODS
  The study design included extraction of all mandibular premolars in five canines . After 2 months, six implants were placed in each dog. Four of them were platform-switched (PS) implants and two were non-platform-switched (NPS) implants. Some or all of the abutments connected to the implants were disconnected at pre-ordained post-surgical intervals. Radiographs were taken at the time of implant placement and at every handling. The values for mesial (horizontal and vertical) and distal (horizontal and vertical) bone resorption were taken and compared for each implant at every abutment dis/reconnection.
  
  
  RESULTS
  The average vertical bone resorption around NPS implants after four dis/reconnections was 1.09 mm (SD 0.25 mm), and the average horizontal bone resorption was 0.98 mm (SD 0.27 mm). The average vertical bone resorption around PS implants after four dis/reconnections was 0.24 mm, (SD 0.08 mm) and the average horizontal bone resorption was 0.24 mm (SD 0.13 mm). The difference of the average horizontal and vertical bone resorption around NPS (site D) and PS (site A) implants was statically significant (P < 0.05). The average mesial and distal bone resorption values around PS (site A) implant adjacent to a tooth were compared, and statically significant differences were found (P < 0.05).
  
  
  CONCLUSIONS
  Implants with a PS design show less peri-implant bone resorption during the healing process and as their abutments are disconnected, than do comparably dis/reconnected NPS implants. The location of the PS implant next to a tooth may decrease radiographically visible peri-implant bone resorption significantly.
authors.affiliation: Private Practice, Barcelona/Madrid, Spain. headquarters@borgroup.net
authors.forename: Xavier
authors.initials: X
authors.lastname: Rodríguez
authors.forename: Xavier
authors.initials: X
authors.lastname: Vela
authors.forename: Víctor
authors.initials: V
authors.lastname: Méndez
authors.forename: Maribel
authors.initials: M
authors.lastname: Segalà
authors.forename: Jose L
authors.initials: JL
authors.lastname: Calvo-Guirado
authors.forename: Dennis P
authors.initials: DP
authors.lastname: Tarnow
mesh_terms: D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging*; D000818:Animals; D001641:Bicuspid; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D004285:Dogs; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery; D011859:Radiography; D014081:Tooth Extraction
chemical_list: D015921:Dental Implants