title: Aging of the mandible and its aesthetic implications.
abstract: BACKGROUND
  Facial aging is a dynamic process involving the aging of soft-tissue and bony structures. In this study, the authors demonstrate how specific bony aspects of the mandible change with age in both genders and what impact these structural changes may have on overall facial aesthetics.
  
  
  METHODS
  Facial bone three-dimensional computed tomographic scans were obtained from 120 Caucasian subjects (60 women and 60 men). Our study population consisted of 20 male and 20 female subjects in each of three age categories (20 to 40, 41 to 64, and > or = 65 years). Edentulous patients were excluded. The following measurements were obtained: bigonial width, ramus breadth, ramus height, mandibular body height, mandibular body length, and mandibular angle. The data were analyzed with one-way analysis of variance and two-tailed t tests, with results considered significant at a value of p < 0.05.
  
  
  RESULTS
  There was no significant change with regard to bigonial width or ramus breadth across age groups for either gender. Ramus height, mandibular body height, and mandibular body length decreased significantly with age for both genders, whereas the mandibular angle increased significantly for both genders with increasing age.
  
  
  CONCLUSIONS
  These results suggest that the bony elements of the mandible change significantly with age for both genders and that these changes, coupled with soft-tissue changes, lead to the appearance of the aged lower third of the face.
authors.affiliation: Rochester, N.Y.; and Stanford, Calif. From the Division of Plastic and Reconstructive Surgery, Department of General Surgery, University of Rochester Medical Center, and the Division of Plastic and Reconstructive Surgery, Department of General Surgery, Stanford University Medical Center.
authors.forename: Robert B
authors.initials: RB
authors.lastname: Shaw
authors.forename: Evan B
authors.initials: EB
authors.lastname: Katzel
authors.forename: Peter F
authors.initials: PF
authors.lastname: Koltz
authors.forename: David M
authors.initials: DM
authors.lastname: Kahn
authors.forename: John A
authors.initials: JA
authors.lastname: Girotto
authors.forename: Howard N
authors.initials: HN
authors.lastname: Langstein
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D002508:Cephalometry; D005260:Female; D006801:Humans; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000502:physiology*; D008875:Middle Aged; D014057:Tomography, X-Ray Computed; D055815:Young Adult