title: Association between regional heterogeneity in the mid-facial bone micro-architecture and increased fragility along Le Fort lines.
abstract: OBJECTIVE
  Le Fort lines have traditionally been considered as zones of weakness in the mid-facial skeleton although the structural basis of increased bone fragility at these sites has not yet been investigated. Considering recent findings of occlusal loading-related regional heterogeneity in the mid-facial bone micro-architecture, the aim of this study was to explore whether such heterogeneity in cortical and cancellous bone micro-architecture may contribute to increased fragility at Le Fort fracture sites.
  
  
  METHODS
  Twenty-five cortical and thirteen cancellous bone specimens were harvested from a dry skull and analyzed by micro-CT. Specimens were classified into Le Fort or Non-Le Fort groups based on their location in the mid-facial skeleton.
  
  
  RESULTS
  Cortical bone along Le Fort lines showed tendencies toward lower thickness (1.5±0.63 vs 1.75±0.79; P=.39) and greater porosity (11.48±5.67 vs 10.28±5.28; P=.59). A significant difference was detected in the trabecular degree of anisotropy which was higher in cancellous bone from Le Fort fracture sites (2.14±0.69 vs 1.58±0.34; P=.02).
  
  
  CONCLUSIONS
  Regional heterogeneity in cortical bone micro-architecture could not fully explain increased fragility of the mid-facial skeleton at the Le Fort lines. However, regional differences in trabecular bone anisotropy may contribute to increased bone fragility.
authors.affiliation: Department of Radiology, Faculty of Dental Medicine, University of Belgrade, Belgrade, Serbia.|Laboratory for Anthropology, Faculty of Medicine, Institute of Anatomy, University of Belgrade, Belgrade, Serbia.|Department of Osteology & Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Aleksa
authors.identifier: http://orcid.org/0000-0002-3084-0022
authors.initials: A
authors.lastname: Janovic
authors.affiliation: Laboratory for Anthropology, Faculty of Medicine, Institute of Anatomy, University of Belgrade, Belgrade, Serbia.|Department of Osteology & Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Petar
authors.initials: P
authors.lastname: Milovanovic
authors.affiliation: Department of Osteology & Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Hahn
authors.affiliation: Department of Radiology, Faculty of Dental Medicine, University of Belgrade, Belgrade, Serbia.
authors.forename: Zoran
authors.initials: Z
authors.lastname: Rakocevic
authors.affiliation: Department of Osteology & Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Amling
authors.affiliation: Department of Osteology & Biomechanics, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
authors.forename: Bjoern
authors.initials: B
authors.lastname: Busse
authors.affiliation: Clinic of Otorhinolaryngology and Maxillofacial Surgery, Faculty of Medicine, Clinical Center of Serbia, University of Belgrade, Belgrade, Serbia.
authors.forename: Milovan
authors.initials: M
authors.lastname: Dimitrijevic
authors.affiliation: Laboratory for Anthropology, Faculty of Medicine, Institute of Anatomy, University of Belgrade, Belgrade, Serbia.
authors.forename: Marija
authors.initials: M
authors.lastname: Djuric
mesh_terms: D059925:Anatomic Landmarks; D015519:Bone Density / Q000502:physiology; D005147:Facial Bones / Q000648:ultrastructure*; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D055114:X-Ray Microtomography
keywords: Le Fort; bone; fracture; micro-architecture; mid-facial skeleton