title: The acceptability of variations in smile arc and buccal corridor space.
abstract: OBJECTIVE
  To evaluate the esthetic acceptability range of computer-generated variations in smile arc and buccal corridor.
  
  
  METHODS
  Web-based descriptive study using available subjects.
  
  
  METHODS
  The World Wide Web. Subjects for the main study included 115 lay and 131 orthodontist raters.
  
  
  METHODS
  Buccal corridors and smile arcs, each presented for a female and a male image. Buccal corridors were presented as none, ideal and excessive. The smile arc was presented as flat, ideal and excessive. The nine male and female variations, as combinations of the above variables, were each presented twice to evaluate reliability.
  
  
  METHODS
  Acceptability of buccal corridors and smile arcs using the web-based instrument. An arbitrary super majority threshold of acceptability was set at 67% approval.
  
  
  RESULTS
  Both laypersons and orthodontists showed good reliability (k >or= 0.70). There was a broad range of acceptability, but laypersons and orthodontists showed no significant differences on the two variables tested. While orthodontists and laypersons both found smiles with excessive buccal corridors to be significantly less acceptable than those with ideal or absent buccal corridors, they were still acceptable over 70% of the time. Flat smile arcs were only acceptable 50-60% of the time, while smiles with ideal and excessive smile arcs were significantly more acceptable 84-95% of the time. When examining buccal corridors and smile arcs together, excessive buccal corridors were significantly less acceptable than ideal or absent buccal corridors regardless of the smile arc. A flat smile arc significantly reduced the acceptability of any buccal corridor to below the threshold of acceptability.
  
  
  CONCLUSIONS
  Laypersons and orthodontists have similar preferences when acceptability of buccal corridors and smile arcs are considered. Flat smile arcs are more detrimental to smile esthetics than variations in buccal corridors. Clinicians must realize that although attractiveness may be reduced by variations in buccal corridors and smile arcs, the result may still be acceptable to a majority of people.
authors.affiliation: Private Practitioner, Dayton, OH, USA.
authors.forename: S
authors.initials: S
authors.lastname: Parekh
authors.forename: H W
authors.initials: HW
authors.lastname: Fields
authors.forename: F M
authors.initials: FM
authors.lastname: Beck
authors.forename: S F
authors.initials: SF
authors.lastname: Rosenstiel
mesh_terms: D001290:Attitude; D001291:Attitude of Health Personnel; D003724:Dental Arch / Q000033:anatomy & histology; D004955:Esthetics, Dental; D005260:Female; D006801:Humans; D020407:Internet; D008046:Lip / Q000033:anatomy & histology*; D008297:Male; D009970:Orthodontics; D010865:Pilot Projects; D015203:Reproducibility of Results; D012904:Smiling / Q000502:physiology*; D014070:Tooth / Q000033:anatomy & histology