title: [Histochemical study and classification of facial muscles fibers].
abstract: OBJECTIVE
  To study the histological and histochemical characteristics of the facial muscle fiber.
  
  
  METHODS
  Seven biopsy specimens of the facial muscle from twelve patients were stained with histochemical method. The diameter and the histochemical type of the fibers were analysed by staining of M-ATP ase and NADA-TR. Type I and type II fibers were evaluated respectively by means of computer-assisted image analysis.
  
  
  RESULTS
  The fiber diameter is between 24.3-63.9 microns. According to the quantity of fiber I, facial muscles may be classified into three groups: 1. Phasic muscle contains less than 20 percent of type I fibers; 2. Intermediate muscle contains 21 to 40 percent of type I fibers; 3. Tonic muscle contains 41 to 69 percent of type I fibers.
  
  
  CONCLUSIONS
  The results of the study show that the histological and histochemical difference of facial muscles may have significance in facial paralysis restoration.
authors.affiliation: Stomatological Department of Rocket Army General Hospital, Beijing 100088, PR China.
authors.forename: Y
authors.initials: Y
authors.lastname: Fa
authors.forename: X
authors.initials: X
authors.lastname: Gu
authors.forename: S
authors.initials: S
authors.lastname: Zhou
mesh_terms: D000328:Adult; D000368:Aged; D001706:Biopsy; D005152:Facial Muscles / Q000473:pathology* / Q000637:transplantation; D005260:Female; D006651:Histocytochemistry; D006801:Humans; D008297:Male; D008875:Middle Aged; D009062:Mouth Neoplasms / Q000601:surgery; D018485:Muscle Fibers, Skeletal / Q000145:classification*; D037981:Neck Dissection