title: Evaluation of factors influencing the marginal bone stability around implants in the treatment of partial edentulism.
abstract: BACKGROUND
  The original protocol of Brånemark to achieve predictable osseointegration for oral implants has substantially been modified. One may question whether results are influenced by those modifications, especially for the long-term prognosis.
  
  
  OBJECTIVE
  The goal of the present study was to investigate the impact of those parameters that deviate from the original protocol as defined by P-I Brånemark.
  
  
  METHODS
  In this study, 246 patients with 263 fixed partial prostheses supported by 668 Brånemark implants were followed from 1 to 15 years (mean: 6.3 yr). Radiographs were taken at the time of abutment connection, at 3 to 6 months, at 12 months, and then every 3 years. The bone level was rated mesially and distally from the implants on a total of 2588 radiographs.
  
  
  RESULTS
  A positive relation between abutment length and marginal bone level was found (p > .0001). The maxilla (p = .03), porcelain (p = .007), long abutments (p = .008), and regular-sized diameter implants (p = .001) all exhibited more bone loss in the first 6 months. After 6 months, only long implants showed more bone loss (p = .03).
  
  
  CONCLUSIONS
  Overall, the marginal bone level remained stable around Brånemark implants, never surpassing 2.2 mm, even after 15 years. Although longer implants lost more bone over time, this has to be interpreted with respect to higher resorption rates in less resorbed jaws.
authors.affiliation: Department of Prosthetic Dentistry, School of Dentistry, Catholic University of Leuven, Leuven, Belgium. Ignace Naert@med.kuleuven.ac.be
authors.forename: I
authors.initials: I
authors.lastname: Naert
authors.forename: J
authors.initials: J
authors.lastname: Duyck
authors.forename: M
authors.initials: M
authors.lastname: Hosny
authors.forename: R
authors.initials: R
authors.lastname: Jacobs
authors.forename: M
authors.initials: M
authors.lastname: Quirynen
authors.forename: D
authors.initials: D
authors.lastname: van Steenberghe
mesh_terms: D000328:Adult; D000368:Aged; D001862:Bone Resorption / Q000145:classification / Q000000981:diagnostic imaging; D000044:Dental Abutments; D015921:Dental Implants; D003776:Dental Porcelain; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D003830:Denture, Partial, Fixed; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007576:Jaw, Edentulous, Partially / Q000000981:diagnostic imaging / Q000534:rehabilitation / Q000601:surgery*; D008137:Longitudinal Studies; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008437:Maxilla / Q000000981:diagnostic imaging / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D016348:Osseointegration; D011379:Prognosis; D011859:Radiography; D012044:Regression Analysis; D013499:Surface Properties; D013997:Time Factors
chemical_list: D015921:Dental Implants; D003776:Dental Porcelain