title: Upper lip asymmetry in adults during smiling.
abstract: OBJECTIVE
  This study examined the incidence of upper lip asymmetry in adults while smiling.
  
  
  METHODS
  Two-hundred ten students between the ages of 21 and 44 years were examined. Subjects determined to have an occlusal plane cant were eliminated from the study. Repeated smiles were then evaluated in the remaining subjects to check for upper lip asymmetry.
  
  
  RESULTS
  Fifteen subjects were observed to have occlusal plane cants and were eliminated from the study. Of the remaining 195 subjects, 17 (8.7%) were found to have an asymmetrical smile secondary to canting of the upper lip.
  
  
  CONCLUSIONS
  Although there was not a high incidence, the results of this study indicate there is clinically evident upper lip canting associated with smiling in the adult population that needs to be considered in patients undergoing orthognathic and cosmetic surgery.
authors: Department of Oral and Maxillofacial Surgery, Virginia Commonwealth University, School of Dentistry, Richmond 23298-0566, USA. DMLASKIN@VCU.EDU
authors: K J
authors: KJ
authors: Benson
authors: D M
authors: DM
authors: Laskin
mesh_terms: D000328:Adult; D004955:Esthetics, Dental; D005146:Facial Asymmetry / Q000145:classification*; D005260:Female; D006801:Humans; D015994:Incidence; D008046:Lip / Q000473:pathology*; D008297:Male; D012904:Smiling