title: Effect of food consistency on the degree of mineralization in the rat mandible.
abstract: A switch to a soft diet, associated with reduced forces applied to the mandible during mastication, may result in an alteration of the degree of mineralization in the mandible. This alteration may be regionally different. The aim of this study was to analyze this alteration by examination of the degree of mineralization in the mandible of growing rats fed with a hard or soft diet. Fifteen Wistar male rats were used in this investigation. After weaning, six rats were fed with a hard diet and the remaining nine rats with a soft diet. After 9 weeks, three-dimensional reconstructions of the cortical and trabecular bone of their mandibles were obtained using a microCT system. The degree of mineralization was determined for the trabecular bone in the condyle and for the cortical bone in the anterior and posterior areas of the mandibular body. In both diet groups the degree of mineralization was significantly (p < 0.01) lower in the trabecular than in the cortical bone. In the mandibular body, the anterior area showed a significantly (p < 0.01) higher degree of mineralization than the posterior area in both diet groups. In both areas the soft diet group had a significantly (p < 0.05 or 0.01) higher degree of mineralization than the hard diet group. The trabecular bone in the condyle of the hard diet group showed a significantly (p < 0.01) higher degree of mineralization than in the soft diet group. The present results indicate the importance of proper masticatory muscle function for craniofacial growth and development.
authors.affiliation: Department of Orthodontics and Craniofacial Developmental Biology, Hiroshima University Graduate School of Biomedical Sciences, 1-2-3 Kasumi, Hiroshima 734-8553, Japan. etanaka@hiroshima-u.ac.jp
authors.forename: Eiji
authors.initials: E
authors.lastname: Tanaka
authors.forename: Ryota
authors.initials: R
authors.lastname: Sano
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Kawai
authors.forename: Geerling E J
authors.initials: GE
authors.lastname: Langenbach
authors.forename: Peter
authors.initials: P
authors.lastname: Brugman
authors.forename: Kazuo
authors.initials: K
authors.lastname: Tanne
authors.forename: Theo M G J
authors.initials: TM
authors.lastname: van Eijden
mesh_terms: D000818:Animals; D001835:Body Weight; D002113:Calcification, Physiologic / Q000502:physiology*; D004032:Diet; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000254:growth & development / Q000502:physiology*; D008335:Mandibular Condyle / Q000254:growth & development / Q000502:physiology; D008409:Mastication / Q000502:physiology; D008410:Masticatory Muscles / Q000254:growth & development / Q000502:physiology; D011859:Radiography; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar