RT Book, Section
A1 Baumann, Leslie
A1 Saghari, Sogol
A2 Baumann, Leslie
A2 Saghari, Sogol
A2 Weisberg, Edmund
SR Print(0)
ID 1172445577
T1 Basic Science of the Dermis
T2 Cosmetic Dermatology: Principles and Practice, 2e
YR 2009
FD 2009
PB The McGraw-Hill Companies, Inc.
PP New York, NY
SN 9780071490627
LK dermatology.mhmedical.com/content.aspx?aid=1172445577
RD 2024/04/20
AB The  dermis  lies  between  the  epidermis  and  the  subcutaneous  fat.  It  is  responsible  for  the  thickness  of  the  skin,  and  as  a  result  plays  a  key  role  in  the  cosmetic  appearance  of  the  skin.  The  thickness  of  the  dermis  varies  over  different  parts  of  the  body  and  the  size  doubles  between  the  ages  of  3  and  7  years  and  again  at  puberty.  With  aging,  this  basic  layer  decreases  in  thickness  and  moisture.  The  dermis,  which  is  laden  with  nerves,  blood  vessels,  and  sweat  glands,  consists  mostly  of  collagen.  The  uppermost  portion  of  this  layer,  which  lies  beneath  the  epidermis,  is  known  as  the  papillary  dermis  and  the  lower  portion  is  known  as  the  reticular  dermis.  Smaller  collagen  bundles,  greater  cellularity,  and  a  higher  density  in  its  vascular  elements  characterize  the  papillary  dermis  as  compared  to  the  reticular  dermis.  Fibroblasts  are  the  primary  cell  type  in  the  dermis.  They  produce  collagen,  elastin,  other  matrix  proteins,  and  enzymes  such  as  collagenase  and  stromelysin.  These  structural  components  will  be  discussed  individually  because  each  exhibits  significant  characteristics  that  influence  the  function  of  the  skin.  Immune  cells  such  as  mast  cells,  polymorphonuclear  leukocytes,  lymphocytes,  and  macrophages  are  also  present  in  the  dermis.