title: Crestal bone loss proximal to oral implants in older and younger adults.
abstract: BACKGROUND
  Older adults often have bone loss and may be at risk of bone resorption around oral implants.
  
  
  OBJECTIVE
  This study tested the hypothesis that there is no difference in crestal bone loss proximal to oral implants in the complete implant prosthesis sites of older and younger adults.
  
  
  METHODS
  Two groups of 35 complete dental implant prosthesis sites (23 screw-retained fixed prostheses and 12 bar-retained overdentures) were selected by matching sites in 32 older adults (60 to 74 years old with 166 Bränemark implants) to sites in 34 younger adults (29 to 49 years old with 162 Bränemark implants) on the basis of possible confounding factors including gender, prosthetic design, implant number, arch, year of surgery, and opposing dentition. Statistical comparisons (Mann-Whitney test at P<.05) were made of mean crestal bone level at loading and mean annual crestal bone loss during the first year, first to fourth year, after first year, and after fourth year of loading with periapical radiographic measurements of the vertical distance in millimeters from the apical edge of the implant collar to the most apical initial point of contact between the implant and bone.
  
  
  RESULTS
  No significant differences were found between the groups. Mean bone levels at loading were 1.4 mm below the collar in both groups and mean annual crestal bone loss after the first year of loading was 0.04 mm/y in both groups. However, significant differences were found between some old and young subgroups stratified by arch and prosthetic design.
  
  
  CONCLUSIONS
  Within the limitations of this study, elders should expect no more rapid bone resorption around oral implants in edentulous jaws than that seen in young adults.
authors.affiliation: University of British Columbia, Vancouver, Canada. rbryant@interchange.ubc.ca
authors.forename: S Ross
authors.initials: SR
authors.lastname: Bryant
authors.forename: George A
authors.initials: GA
authors.lastname: Zarb
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000209:etiology*; D001862:Bone Resorption / Q000000981:diagnostic imaging / Q000209:etiology; D016022:Case-Control Studies; D003724:Dental Arch / Q000473:pathology; D015921:Dental Implants; D017267:Dental Prosthesis Design; D019094:Dental Prosthesis, Implant-Supported; D003828:Denture, Overlay; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007571:Jaw Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011859:Radiography; D012737:Sex Factors; D018709:Statistics, Nonparametric
chemical_list: D015921:Dental Implants