title: Stability of contour augmentation and esthetic outcomes of implant-supported single crowns in the esthetic zone: 3-year results of a prospective study with early implant placement postextraction.
abstract: BACKGROUND
  Early implant placement is one of the treatment options after tooth extraction. Implant surgery is performed after a healing period of 4 to 8 weeks and combined with a simultaneous contour augmentation using the guided bone regeneration technique to rebuild stable esthetic facial hard- and soft-tissue contours.
  
  
  METHODS
  In this prospective study, 20 patients were treated with an implant-born single crown and followed for 3 years. Clinical, radiologic, and esthetic parameters were recorded to assess treatment outcomes.
  
  
  RESULTS
  At the 3-year examination, all 20 implants were successfully integrated, demonstrating ankylotic stability and healthy peri-implant soft tissues as documented by standard clinical parameters. Esthetic outcomes were assessed by the pink esthetic score (PES) and white esthetic score (WES) and confirmed pleasing results overall. WES values were slightly superior to PES values. Periapical radiographs showed minimal crestal bone loss around used bone-level implants with a mean bone loss of 0.18 mm at 3 years. Only two implants revealed bone loss between 0.5 and 1.0 mm. One of these implants had minor mucosal recession <1.0 mm.
  
  
  CONCLUSIONS
  This prospective study evaluates the concept of early implant placement and demonstrated successful tissue integration for all 20 implants and stable bone-crest levels around implant-abutment interfaces according to the platform-switching concept. The midterm 3-year follow-up revealed pleasing esthetic outcomes and stable facial soft tissues. The risk of mucosal recession was low, with only one patient showing minor recession of the facial mucosa. These encouraging results need to be confirmed with a 5-year follow-up examination.
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Bern, Switzerland. daniel.buser@zmk.unibe.ch
authors.forename: Daniel
authors.initials: D
authors.lastname: Buser
authors.forename: Julia
authors.initials: J
authors.lastname: Wittneben
authors.forename: Michael M
authors.initials: MM
authors.lastname: Bornstein
authors.forename: Linda
authors.initials: L
authors.lastname: Grütter
authors.forename: Vivianne
authors.initials: V
authors.lastname: Chappuis
authors.forename: Urs C
authors.initials: UC
authors.lastname: Belser
mesh_terms: D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging; D000540:Alveolar Ridge Augmentation / Q000379:methods*; D001861:Bone Regeneration; D003442:Crowns; D000044:Dental Abutments; D003758:Dental Implantation, Endosseous / Q000379:methods*; D019250:Dental Implants, Single-Tooth; D017267:Dental Prosthesis Design; D004955:Esthetics, Dental; D005889:Gingival Recession / Q000517:prevention & control; D016557:Guided Tissue Regeneration, Periodontal; D006801:Humans; D007180:Incisor; D008437:Maxilla; D011446:Prospective Studies; D011859:Radiography; D020390:Tooth Socket / Q000601:surgery; D016896:Treatment Outcome