title: A ³¹P-magnet resonance spectroscopy study on the metabolism of human masseter in individuals with different vertical facial pattern.
abstract: OBJECTIVE
  The objective of this study was to investigate differences in masseter metabolism by (31)P-Chemical Shift Imaging (CSI) in adult individuals with different vertical facial patterns. The clinical study should be supported by functional findings at the mRNA level after orthognathic surgery.
  
  
  METHODS
  Twenty-two male volunteers (mean age 24.6) were divided into a deep-bite (NL/ML 11.8 ± 2.3°) and open-bite group (NL/ML 34.1 ± 2.6°). Vertical jaw relationship, gonial angle, and masseter volume were defined and compared with the phosphate values obtained from the (31)P spectra. Student t test and regression analysis were used.
  
  
  RESULTS
  Phosphocreatine related strongly to muscle volume (P < .001), gonial angle (P < .001), and ML/NL angle (P < .01). Pi was found to be related to gonial angle (P < .05). Muscle volume was found to be inversely related to ML/NL (P < .01) and to the gonial angle (P < .01).
  
  
  CONCLUSIONS
  A difference in masseter muscle metabolism between long- and short-faced subjects was confirmed at rest position.
authors: Department of Orthodontics, Technical University of Dresden, Dresden, Germany. claudiagregor@ymail.com
authors: Claudia
authors: C
authors: Gregor
authors: Volker
authors: V
authors: Hietschold
authors: Winfried
authors: W
authors: Harzer
mesh_terms: D000328:Adult; D002508:Cephalometry / Q000379:methods; D004734:Energy Metabolism / Q000502:physiology; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D008334:Mandible / Q000473:pathology; D008406:Masseter Muscle / Q000378:metabolism* / Q000473:pathology; D009119:Muscle Contraction / Q000502:physiology; D024343:Open Bite / Q000378:metabolism* / Q000473:pathology; D009929:Organ Size; D057887:Overbite / Q000378:metabolism* / Q000473:pathology; D010710:Phosphates / Q000032:analysis; D010725:Phosphocreatine / Q000032:analysis; D010759:Phosphorus Isotopes; D012146:Rest / Q000502:physiology; D014716:Vertical Dimension; D055815:Young Adult
chemical_list: D010710:Phosphates; D010759:Phosphorus Isotopes; D010725:Phosphocreatine