title: Peri-implant bone level around implants with platform-switched abutments.
abstract: OBJECTIVE
  The purpose of this clinical trial was to evaluate whether the crestal bone height around dental implants could be influenced by the use of a platform-switching protocol.
  
  
  METHODS
  All implants placed in the year 2006 in healed bone without any need for ridge augmentation were included in this study. The following groups were created: (1) wide-diameter implants were placed subcrestally and regular-diameter cover screws were connected; (2) regular-diameter implants were placed at the crest and regular-diameter cover screws were connected. Standardized radiographs were obtained after insertion of the definitive prosthesis and after 1 year. Calibrated measurements were conducted initiating from the mesial and distal bone peaks to the implant-abutment junction. The average value of the mean medial and mean distal values was calculated and analyzed with an unpaired two-tailed t test. P values < .05 were regarded as statistically significant.
  
  
  RESULTS
  In all, 89 dental implants in 36 patients were evaluated. The implants with a platform-switched configuration (n = 75) exhibited statistically significantly less bone loss at time of insertion of the definitive prosthesis (0.30 +/- 0.07 mm versus 0.68 +/- 0.17 mm; P < .05) and at 1 year (0.39 +/- 0.07 mm versus 1.00 +/- 0.22 mm, P < .01) when compared to the nonplatform-switched implants (n = 14).
  
  
  CONCLUSIONS
  Platform-switched implants seem to limit crestal bone remodeling.
authors.affiliation: Department of Periodontology, Julius Maximilians-University, Würzburg, Germany. fickl_s@klinik.uni-wuerzburg.de
authors.forename: Stefan
authors.initials: S
authors.lastname: Fickl
authors.forename: Otto
authors.initials: O
authors.lastname: Zuhr
authors.forename: Jamal M
authors.initials: JM
authors.lastname: Stein
authors.forename: Markus B
authors.initials: MB
authors.lastname: Hürzeler
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000209:etiology*; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000009:adverse effects*; D015921:Dental Implants; D017267:Dental Prosthesis Design; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged
chemical_list: D015921:Dental Implants