title: Sagging of the cheek is related to skin elasticity, fat mass and mimetic muscle function.
abstract: OBJECTIVE
  Facial sagging is associated with aging, although the mechanism remains unclear. The aim of this study was to investigate the mechanism of facial sagging by examining the relationship of sagging severity to changes of skin elasticity, fat mass and facial muscle function at the cheek.
  
  
  METHODS
  Faces of 108 healthy Japanese female volunteers, aged 20-60 years were photographed at an angle of 45 degrees . Standard scores of sagging severity were established by analyzing the photographs. We examined the correlations of scored sagging levels with skin elasticity measured with a Cutometer MPA 580, fat content estimated by bioelectrical impedance analysis and facial muscle function (lip sealing force and occlusal force) in middle-aged female volunteers (30-40 years) with a wide range of sagging scores.
  
  
  RESULTS
  Because the upper, lower and lateral areas in the cheek may show severe sagging, a six-grade score of sagging severity was separately established for each area. Each score was significantly correlated positively with age (20-60 years). In middle-aged volunteers, the sagging scores in all three areas of the cheek were significantly and negatively associated with skin elasticity. Body fat percentage was significantly and positively correlated with the sagging scores in the lower and lateral areas, although the correlation was only weakly positive in the upper area. Mimetic muscle function, measured in terms of lip sealing pressure, was significantly and negatively correlated with the sagging score only at the upper area of the cheek, but masticatory muscle function, measured in terms of occlusal force pressure, was not associated with the sagging score.
  
  
  CONCLUSIONS
  Sagging may be associated with the reduction of skin elasticity and mimetic muscle function and increase of fat mass, but the relationships are different in different areas of the cheek.
authors.affiliation: Shiseido Life Science Research Center, 2-2-1 Hayabuchi, Tsuzuki-ku, Yokohama-shi, Kanagawa 224-8558, Japan. tomonobu.ezure@to.shiseido.co.jp
authors.forename: T
authors.initials: T
authors.lastname: Ezure
authors.forename: J
authors.initials: J
authors.lastname: Hosoi
authors.forename: S
authors.initials: S
authors.lastname: Amano
authors.forename: T
authors.initials: T
authors.lastname: Tsuchiya
mesh_terms: D000273:Adipose Tissue / Q000502:physiology*; D000293:Adolescent; D000328:Adult; D000375:Aging / Q000473:pathology / Q000502:physiology*; D032701:Biomimetics / Q000379:methods; D002610:Cheek / Q000033:anatomy & histology / Q000502:physiology*; D055119:Elastic Modulus / Q000502:physiology; D005260:Female; D006801:Humans; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000033:anatomy & histology / Q000502:physiology*; D009929:Organ Size / Q000502:physiology; D012867:Skin / Q000033:anatomy & histology; D015595:Skin Aging / Q000502:physiology*; D055815:Young Adult