title: Immediate and early loading of chemically modified implants in posterior jaws: 3-year results from a prospective randomized multicenter study.
abstract: BACKGROUND
  There is a lack of well-designed prospective, randomized clinical trials evaluating the efficacy of immediate and early loading of implants placed in the partially edentulous posterior maxilla or mandible.
  
  
  OBJECTIVE
  The aim of this study was to evaluate crestal bone level changes over 3 years following immediate or early loading of Straumann implants with a chemically modified surface (SLActive®, Institut Straumann AG, Basel, Switzerland) placed in the posterior maxilla and mandible.
  
  
  METHODS
  Subjects received temporary restorations immediately or 28 to 34 days after surgery, with permanent restorations placed at 20 to 23 weeks. Bone level changes were measured by comparison of standardized radiographs taken on the day of implant placement and 5, 12, 24, and 36 months thereafter.
  
  
  RESULTS
  Two hundred thirty-nine of two hundred sixty-six patients (89.9%) completed the trial. Implant survival rates were 97.4% and 96.7% in the immediate and early loading groups, respectively (p = not significant). Over 36 months, the mean bone level change for immediately loaded implants was 0.88 ± 0.81 mm versus 0.57 ± 0.83 mm for the early-loaded group (p < .001). After adjusting for a slight difference in initial placement depth, the time of loading had no significant influence on bone level change.
  
  
  CONCLUSIONS
  Changes in crestal bone level occurred mostly during the first 5 months postloading. After this bone remodeling period, crestal bone level was stable up to 36 months. Implants with a chemically modified surface are safe and predictable for immediate and early loading in the posterior maxilla and mandible.
authors.affiliation: Faculty of Medicine, University of Coimbra, Coimbra, Portugal. pgnicolau@mail.telepac.pt
authors.forename: Pedro
authors.initials: P
authors.lastname: Nicolau
authors.forename: Jonathan
authors.initials: J
authors.lastname: Korostoff
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Ganeles
authors.forename: Jochen
authors.initials: J
authors.lastname: Jackowski
authors.forename: Tim
authors.initials: T
authors.lastname: Krafft
authors.forename: Manuel
authors.initials: M
authors.lastname: Neves
authors.forename: Jose
authors.initials: J
authors.lastname: Divi
authors.forename: Michael
authors.initials: M
authors.lastname: Rasse
authors.forename: Fernando
authors.initials: F
authors.lastname: Guerra
authors.forename: Kerstin
authors.initials: K
authors.lastname: Fischer
mesh_terms: D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging; D000539:Alveolar Process / Q000000981:diagnostic imaging; D015519:Bone Density / Q000502:physiology; D016723:Bone Remodeling / Q000502:physiology; D003442:Crowns; D003724:Dental Arch / Q000000981:diagnostic imaging / Q000601:surgery; D015921:Dental Implants; D017267:Dental Prosthesis Design; D003794:Dental Restoration, Temporary; D003830:Denture, Partial, Fixed; D003833:Denture, Partial, Temporary; D005500:Follow-Up Studies; D006801:Humans; D057893:Immediate Dental Implant Loading / Q000379:methods*; D007576:Jaw, Edentulous, Partially / Q000534:rehabilitation / Q000601:surgery*; D008334:Mandible / Q000000981:diagnostic imaging / Q000601:surgery*; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery*; D008875:Middle Aged; D016348:Osseointegration / Q000502:physiology; D016300:Radiography, Bitewing / Q000379:methods; D013499:Surface Properties; D016019:Survival Analysis
chemical_list: D015921:Dental Implants