title: Radiographic evaluation of conical tapered platform-switched implants in the posterior mandible: 1-year results of a two-center prospective study.
abstract: OBJECTIVE
  Long-term success of dental implants depends on healthy peri-implant soft tissues and adequate bone levels. This prospective study aims to assess bone level changes around implants with internal conical connection and platform-switching abutments in the posterior mandible.
  
  
  METHODS
  Adult patients missing at least two teeth in the posterior mandible and with a natural tooth mesial to the implant site received two or three adjacent internal conical connection implants. After a minimum transmucosal healing period of 8 weeks, single crown restorations were cemented over platform-switching abutments. Changes in marginal bone levels were measured in standardized periapical radiographs from surgery and loading (baseline) to 12 months post-loading.
  
  
  RESULTS
  Twenty-four patients received 52 implants. Bone remodeling took place between surgery and loading (-0.53 ± 0.40 mm). From loading to 12 months, there was a mean bone gain of 0.12 ± 0.42 mm which occurred mainly in the first 6 months after prosthesis delivery (0.11 ± 0.36 mm) and stabilized afterward. A total of 71.7% of all implants presented bone preservation or gain. No implant was lost at 1 year and the success rate was 100%. Patient inquiry revealed high satisfaction.
  
  
  CONCLUSIONS
  Internal conical connection implants with platform-switching abutments presented high success rate and enhancement or preservation of marginal bone levels after 1 year of loading.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Johannes Gutenberg-University, Medical Centre, Mainz, Germany.
authors.forename: Maximilian
authors.initials: M
authors.lastname: Moergel
authors.affiliation: Department of Dentistry, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Salomão
authors.initials: S
authors.lastname: Rocha
authors.affiliation: Department of Dentistry, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Ana
authors.identifier: http://orcid.org/0000-0003-4019-9379
authors.initials: A
authors.lastname: Messias
authors.affiliation: Department of Dentistry, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Pedro
authors.initials: P
authors.lastname: Nicolau
authors.affiliation: Department of Dentistry, Faculty of Medicine, University of Coimbra, Coimbra, Portugal.
authors.forename: Fernando
authors.initials: F
authors.lastname: Guerra
authors.affiliation: Department of Oral and Maxillofacial Surgery, Johannes Gutenberg-University, Medical Centre, Mainz, Germany.
authors.forename: Wilfried
authors.initials: W
authors.lastname: Wagner
mesh_terms: D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000601:surgery*; D003442:Crowns; D059605:Dental Implant-Abutment Design; D015921:Dental Implants; D019094:Dental Prosthesis, Implant-Supported; D005260:Female; D005858:Germany; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging* / Q000601:surgery*; D008875:Middle Aged; D017060:Patient Satisfaction; D010865:Pilot Projects; D011174:Portugal; D011446:Prospective Studies; D011795:Surveys and Questionnaires
chemical_list: D015921:Dental Implants
keywords: bone level; bone remodeling; conical connection implants; dental implant; outcome; platform switch