title: Insight into bone-derived biological apatite: ultrastructure and effect of thermal treatment.
abstract: OBJECTIVE
  This study aims at examining the ultrastructure of bone-derived biological apatite (BAp) from a series of small vertebrates and the effect of thermal treatment on its physiochemical properties.
  
  
  METHODS
  Femurs/fin rays and vertebral bodies of 5 kinds of small vertebrates were firstly analyzed with X-ray microtomography. Subsequently, BAp was obtained with thermal treatment and low power plasma ashing, respectively. The properties of BAp, including morphology, functional groups, and crystal characteristics were then analyzed.
  
  
  RESULTS
  The bones of grouper and hairtail were mainly composed of condensed bone. Spongy bone showed different distribution in the bones from frog, rat, and pigeon. No significant difference was found in bone mineral density of condensed bone and trabecular thickness of spongy bone. Only platelet-like crystals were observed for BAp obtained by plasma ashing, while rod-like and irregular crystals were both harvested from the bones treated by sintering. A much higher degree of crystallinity and larger crystal size but a lower content of carbonate were detected in the latter.
  
  
  CONCLUSIONS
  Platelet-like BAp is the common inorganic component of vertebrate bones. BAp distributing in condensed and spongy bone may exhibit differing thermal reactivity. Thermal treatment may alter BAp's in vivo structure and composition.
authors.affiliation: Dental Materials Science, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong.
authors.forename: Quan
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Shenzhen Key Laboratory of Marine Biomaterials, Shenzhen Institute of Advanced Technology, Chinese Academy of Science, Shenzhen 518055, China.
authors.forename: Haobo
authors.initials: H
authors.lastname: Pan
authors.affiliation: Department of Oral Implantology, Hospital of Stomatology, Guanghua School of Stomatology, Institute of Stomatological Research, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055, China.
authors.forename: Zhuofan
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Dental Materials Science, Faculty of Dentistry, The University of Hong Kong, Pokfulam, Hong Kong.
authors.forename: Jukka Pekka
authors.initials: JP
authors.lastname: Matinlinna
mesh_terms: D058500:Animal Fins / Q000737:chemistry* / Q000648:ultrastructure*; D000818:Animals; D001001:Anura / Q000502:physiology; D001031:Apatites / Q000737:chemistry*; D015519:Bone Density / Q000502:physiology; D010856:Columbidae / Q000502:physiology; D005269:Femur / Q000737:chemistry* / Q000648:ultrastructure*; D005399:Fishes / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013904:Thoracic Vertebrae / Q000737:chemistry* / Q000648:ultrastructure*; D014714:Vertebrates / Q000502:physiology; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D001031:Apatites