title: Esthetics and smile characteristics evaluated by laypersons.
abstract: OBJECTIVE
  To collect data regarding Canadian laypersons' perceptions of smile esthetics and compare these data to US data in order to evaluate cultural differences.
  
  
  METHODS
  Using Adobe Photoshop 7, a digital image of a posed smile of a sexually ambiguous lower face was prepared so that hard and soft tissue could be manipulated to alter buccal corridor (BC), gingival display (GD), occlusal cant (OC), maxillary midline to face discrepancy (MMFD), and lateral central gingival discrepancy (LCGD). Adult Canadian laypersons (n  =  103) completed an interactive computer-based survey of 29 randomized images to compare smile preferences for these variables. The custom survey was developed to display fluid, continuously appearing modifiable smile variables using MATLAB R2008 for presentation. These data were compared with previously published data for US laypersons. Statistical inference was determined using Wilcoxon rank sum tests.
  
  
  RESULTS
  Canadian laypersons were more sensitive in detecting deviations from ideal and had a narrower range of acceptability thresholds for BC, GD, OC, MMFD, and LCGD. Ideal esthetic values were significantly different only for BC.
  
  
  CONCLUSIONS
  It appears that cultural differences do exist related to smile characteristics. Clinically significant differences in the preference of the smile characteristics were found between Canadian and US laypersons. Canadian laypersons, on average, were more discriminating to deviations from ideal and had a narrower range of acceptability.
authors.affiliation: University of Manitoba, Winnipeg, Canada.
authors.forename: Catherine
authors.initials: C
authors.lastname: McLeod
authors.forename: H W
authors.initials: HW
authors.lastname: Fields
authors.forename: Frank
authors.initials: F
authors.lastname: Hechter
authors.forename: William
authors.initials: W
authors.lastname: Wiltshire
authors.forename: Wellington
authors.initials: W
authors.lastname: Rody
authors.forename: James
authors.initials: J
authors.lastname: Christensen
mesh_terms: D000328:Adult; D002170:Canada; D003431:Cross-Cultural Comparison; D004955:Esthetics, Dental; D006801:Humans; D007091:Image Processing, Computer-Assisted; D011639:Public Opinion; D012904:Smiling; D018709:Statistics, Nonparametric; D014481:United States