title: Alignment of biological apatite crystallites at first molar in human mandible cortical bone.
abstract: The aim of this study was to quantitatively clarify the c-axis alignment of biological apatite (BAp) crystallites (hereafter referred to as BAp alignment) in the cortical bone of the human mandible first molar. Six mandible specimens were collected from the cadavers of six dentulous Japanese adults (mean age, 63.0 +/- 12.1 years) held at the Department of Anatomy, Tokyo Dental College. A microbeam x-ray diffraction system was used to determine BAp alignment in the mesiodistal direction. Bone mineral density (BMD) was also measured using 3-dimensional trabecular structure measurement software. The results showed that the degree of BAp alignment in the mesiodistal direction was low in the alveolar area and high at the base of the mandible, suggesting that BAp alignment in the alveolar area is affected by occlusal force. Moreover, it was observed that the correlation between BAp alignment and BMD was small, indicating that BAp alignment and BMD could be independent factors. Therefore, determining BAp alignment was important in the evaluation of bone quality, including bone strength.
authors.affiliation: Department of Oral and Maxillofacial Implantology at Tokyo Dental College, Chiba, Japan.
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Morioka
authors.forename: Satoru
authors.initials: S
authors.lastname: Matsunaga
authors.forename: Masao
authors.initials: M
authors.lastname: Yoshinari
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Ide
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Nakano
authors.forename: Hideshi
authors.initials: H
authors.lastname: Sekine
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Yajima
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000539:Alveolar Process / Q000648:ultrastructure; D001031:Apatites / Q000737:chemistry*; D001732:Bite Force; D015519:Bone Density / Q000502:physiology; D002102:Cadaver; D003461:Crystallography; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D008334:Mandible / Q000648:ultrastructure*; D008875:Middle Aged; D008963:Molar; D013314:Stress, Mechanical; D014961:X-Ray Diffraction / Q000379:methods; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D001031:Apatites