title: The effects of interimplant distances on papilla formation and crestal resorption in implants with a morse cone connection and a platform switch: a histomorphometric study in dogs.
abstract: BACKGROUND
  Implant esthetics have been the focus of attention for the last few years, and one of the most important points is the effect that interimplant distances can have on papilla formation and bone loss. The aim of this study was to evaluate the effect that distances of 1, 2, and 3 mm between implants after prosthetic restoration will have on crestal bone resorption (from the top of the implant to the bone crest [TI-BC]) and bone resorption (from the top of the implant to the first bone-to-implant contact TI-BIC) in two-stage implants used in a submerged and non-submerged protocol.
  
  
  METHODS
  The mandibular bilateral premolars of seven dogs were extracted, and after 12 weeks, each dog received eight implants. The implants were placed so that three interimplant contact points were created, with 1-mm (group 1), 2-mm (group 2), and 3-mm (group 3) distances constructed on each side. The sides and the position of the groups were randomly selected. After 12 weeks, the implants received metallic prostheses with 5 mm between the contact point and the bone crest. After 8 weeks more, the animals were sacrificed.
  
  
  RESULTS
  The TI-BC was 0.20 and 0.18 mm for group 1, 0.15 and 0.14 mm for group 2, and 0.15 and 0.15 mm for group 3 for non-submerged and submerged implants, respectively. At the proximal region, the TI-BC was 0.16 mm for non-submerged and 0.16 mm for submerged implants. The TI-BIC was 0.32 and 0.30 mm for group 1, 0.19 and 0.21 mm for group 2, and 0.30 and 0.24 mm for group 3 for non-submerged and submerged implants, respectively. At the proximal region, the TI-BIC was 0.26 mm for non-submerged and 0.25 mm for submerged implants. There was no statistical difference for any of the parameters (analysis of variance [ANOVA]).
  
  
  CONCLUSIONS
  Distances of 1, 2, and 3 mm between implants do not result in statistically significant differences on TI-BC and TI-BIC around submerged or non-submerged implants with a Morse cone connection and a platform switch.
authors.affiliation: Department of Bucco-Maxillo-Facial Surgery and Traumatology and Periodontology, School of Dentistry of Ribeirão Preto, University of São Paulo, Ribeirão Preto, SP, Brazil. novaesjr@forp.usp.br
authors.forename: Arthur B
authors.initials: AB
authors.lastname: Novaes
authors.forename: Rafael R
authors.initials: RR
authors.lastname: de Oliveira
authors.forename: Valdir A
authors.initials: VA
authors.lastname: Muglia
authors.forename: Vula
authors.initials: V
authors.lastname: Papalexiou
authors.forename: Mário
authors.initials: M
authors.lastname: Taba
mesh_terms: D016301:Alveolar Bone Loss / Q000209:etiology*; D000818:Animals; D003442:Crowns; D003758:Dental Implantation, Endosseous / Q000009:adverse effects / Q000379:methods*; D017267:Dental Prosthesis Design / Q000295:instrumentation; D017268:Dental Prosthesis Retention / Q000295:instrumentation; D019094:Dental Prosthesis, Implant-Supported; D004285:Dogs; D005881:Gingiva / Q000502:physiology*; D020007:Implants, Experimental; D008297:Male; D016348:Osseointegration