title: Soft diet causes greater alveolar osteopenia in the mandible than in the maxilla.
abstract: OBJECTIVE
  To investigate changes in the bony microstructure of the upper and lower alveolar bone during masticatory loading induced by soft diet feeding in growing rats.
  
  
  METHODS
  Three-week-old male Wistar rats were randomly divided into two groups. Rats were fed with either pellets [control group (n=6)] or a soft diet [experimental group (n=6)] for nine weeks. 3D-microstructure of the alveolar bone of the first molar region (M1) was examined by micro-CT analysis.
  
  
  RESULTS
  Micro-CT images showed increased marrow spaces of the inter-radicular alveolar bone around the rat mandibular M1 in the experimental group compared with that in the control group. The bone volume/tissue volume ratio, trabecular thickness, trabecular number, mean intercept length, trabecular width and trabecular star volume for the mandibular M1 inter-radicular alveolar bone were lower in the experimental group than in the control group. Marrow space star volume was increased in the experimental group compared with the control group.
  
  
  CONCLUSIONS
  These results suggest that alveolar osteopenia is more extensive in the mandible than the maxilla in rats that experience low masticatory loading during growth.
authors.affiliation: Orthodontic Science, Department of Orofacial Development and Function, Division of Oral Health Sciences, Graduate School, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8549, Japan. y.shimizu.orts@tmd.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Shimizu
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Ishida
authors.forename: Jun
authors.initials: J
authors.lastname: Hosomichi
authors.forename: Sawa
authors.initials: S
authors.lastname: Kaneko
authors.forename: Kasumi
authors.initials: K
authors.lastname: Hatano
authors.forename: Takashi
authors.initials: T
authors.lastname: Ono
mesh_terms: D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging / Q000209:etiology*; D000539:Alveolar Process / Q000000981:diagnostic imaging; D000818:Animals; D001732:Bite Force; D001835:Body Weight; D015519:Bone Density / Q000502:physiology; D001851:Bone Diseases, Metabolic / Q000000981:diagnostic imaging / Q000209:etiology*; D001853:Bone Marrow / Q000000981:diagnostic imaging; D004032:Diet / Q000009:adverse effects*; D005502:Food; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008336:Mandibular Diseases / Q000145:classification* / Q000000981:diagnostic imaging / Q000209:etiology; D008409:Mastication / Q000502:physiology; D008439:Maxillary Diseases / Q000000981:diagnostic imaging / Q000209:etiology*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D055114:X-Ray Microtomography / Q000379:methods