title: Skin indentation firmness and tissue dielectric constant assessed in face, neck, and arm skin of young healthy women.
abstract: OBJECTIVE
  Our goal was to test the hypothesis that skin firmness correlates with skin hydration.
  
  
  METHODS
  Dermal water was assessed by tissue dielectric constant (TDC) at 0.5 mm (TDC0.5) and 2.5 mm (TDC2.5) depths on four face sites and two arm sites of 35 women (25.0 ± 1.6 years). Firmness was determined by force (mN) to indent skin to 0.3 mm (F0.3) and 1.3 mm (F1.3).
  
  
  RESULTS
  F0.3was similar among face sites (avg = 16.2 ± 7.2 mN) but F1.3varied (avg = 32.5 ± 4.1 mN). TDC2.5was similar among face sites (avg = 37.7 ± 4.2) but TDC0.5varied (avg = 36.2 ± 4.8). F1.3of arm sites was similar (avg = 60.2 ± 18.6 mN) and both greater than F1.3of neck (28.3 ± 7.1 mN) and face. Regression analysis showed a near-zero correlation between forces and TDC at all sites.
  
  
  CONCLUSIONS
  The near-zero correlation may be due to low skin interstitial hydraulic resistance to mobile water movement in healthy young skin. If true, then conditions in which dermal hydraulic conductance is reduced as in lymphedematous, diabetic, or aged skin are more likely show the hypothesized relationship. Our findings provide normalized reference values and suggest that such persons are an important population to study to test for a possible skin water-indentation force relationship and its utilization for early diagnosis.
authors.affiliation: College of Medical Sciences, Nova Southeastern University, Ft. Lauderdale, FL, USA.
authors.forename: Harvey N
authors.initials: HN
authors.lastname: Mayrovitz
authors.affiliation: College of Osteopathic Medicine, Nova Southeastern University, Ft. Lauderdale, FL, USA.
authors.forename: Kelly
authors.initials: K
authors.lastname: Corbitt
authors.affiliation: College of Osteopathic Medicine, Nova Southeastern University, Ft. Lauderdale, FL, USA.
authors.forename: Alexandra
authors.initials: A
authors.lastname: Grammenos
authors.affiliation: College of Osteopathic Medicine, Nova Southeastern University, Ft. Lauderdale, FL, USA.
authors.forename: Allen
authors.initials: A
authors.lastname: Abello
authors.affiliation: College of Osteopathic Medicine, Nova Southeastern University, Ft. Lauderdale, FL, USA.
authors.forename: Jason
authors.initials: J
authors.lastname: Mammino
mesh_terms: D000293:Adolescent; D000328:Adult; D001132:Arm / Q000502:physiology; D001834:Body Water / Q000378:metabolism*; D055119:Elastic Modulus / Q000502:physiology*; D017097:Electric Impedance; D005145:Face / Q000502:physiology; D005260:Female; D005712:Galvanic Skin Response / Q000502:physiology*; D006244:Hardness / Q000502:physiology*; D006245:Hardness Tests / Q000379:methods*; D006801:Humans; D008597:Menstrual Cycle / Q000502:physiology; D009333:Neck / Q000502:physiology; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012879:Skin Physiological Phenomena; D055815:Young Adult
keywords: edema; lymphedema; skin dielectric constant; skin fibrosis; skin softness; skin water