title: Skin wrinkling morphology changes suddenly in the early 30s.
abstract: OBJECTIVE
  Does the morphology of wrinkles alter gradually with aging or suddenly at a certain age? On the basis of the theoretic wrinkle simulation of ideal skin, we have suggested that the wrinkle morphology suddenly changes from stratum corneum wrinkling to epidermis wrinkling; the former induces shallow fine furrows, and the latter induces deep prominent wrinkles. To examine the existence of drastic change in wrinkling morphology, we developed a new measurement system for facial skin wrinkling test.
  
  
  METHODS
  The mechanical compression test of facial skin was carried out for 102 Japanese women aged 25-56 years. The test was performed on the right temple area skin, and the area of wrinkles induced by the compression was measured using a digital video camera. The rate of increase in wrinkle area during compression was defined as the skin wrinkling rate, and it was calculated for all subjects automatically by image processing.
  
  
  RESULTS
  The test results showed that the skin wrinkling rate underwent a step increase at the age 33, which means that the wrinkling morphologies of young and old skins are completely different, and so it changes suddenly in the early 30s.
  
  
  CONCLUSIONS
  A new skin measurement system was developed to validate our theory of wrinkle formation mechanism with aging. The results demonstrated the wrinkling morphology changes suddenly at early 30s.
authors.affiliation: Department of Nuclear Power & Energy Safety Engineering, University of Fukui, Fukui, Japan. kuwa@u-fukui.ac.jp
authors.forename: Osamu
authors.initials: O
authors.lastname: Kuwazuru
authors.forename: Kukizo
authors.initials: K
authors.lastname: Miyamoto
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Yoshikawa
authors.forename: Shuhei
authors.initials: S
authors.lastname: Imayama
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008875:Middle Aged; D010173:Palpation / Q000379:methods*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D015595:Skin Aging / Q000473:pathology* / Q000502:physiology*; D012882:Skin Tests / Q000379:methods*