title: Three-dimensional bone structure and bone mineral density evaluations of autogenous bone graft after sinus augmentation: a microcomputed tomography analysis.
abstract: OBJECTIVE
  The purpose of this study was to determine the relationships and differences in three-dimensional (3D) bone mineral density (BMD) and microtrabecular structures between autogenous bone grafts and their adjacent native bone after a healing period following maxillary sinus augmentation.
  
  
  METHODS
  Nine rod-shaped human bone biopsy samples were taken from patients receiving two-stage sinus augmentation therapy in implantation areas and analyzed using microcomputed tomography (micro-CT). Before micro-CT scanning, two BMD phantoms were placed near to the bone biopsy samples for executing BMD calculations of the grafted and native bone samples. In addition, 3D structural parameters of the trabeculae were analyzed for both the grafted and native bone, including percentage of bone volume [bone volume (BV)/tissue volume (TV)], bone-specific surface [bone surface (BS)/BV], trabecular thickness (Tb.Th), trabecular number (Tb.N), trabecular separation (Tb.Sp), trabecular pattern factor (Tb.Pf), and structure model index (SMI).
  
  
  RESULTS
  No significant correlations with regard to BMD and trabecular-structure parameters were found between native bone and grafted bone; however, BS/BV and Tb.Pf were higher and Tb.Th and Tb.Sp were 37.35% and 12.74% lower in grafted bone than in native bone. For grafted bone, there were significant correlations (P < 0.05) between BMD and BV/TV, and Tb.N.
  
  
  CONCLUSIONS
  When using autogenous bone as a graft material, BMD and micromorphological conditions of grafted bone were not influenced by the condition of the native bone in the maxilla. Differences were found in surface complexity, trabecular thickness, trabecular separation, and the connectivity of trabeculae between grafted and native bone. The BMD in grafted bone was affected by the quantity of the trabeculae.
authors.affiliation: School of Dentistry, China Medical University, 91 Hsueh-Shih Road, Taichung, Taiwan. hlhuang@mail.cmu.edu.tw
authors.forename: Heng-Li
authors.initials: HL
authors.lastname: Huang
authors.forename: Michael Y C
authors.initials: MY
authors.lastname: Chen
authors.forename: Jui-Ting
authors.initials: JT
authors.lastname: Hsu
authors.forename: Yu-Fen
authors.initials: YF
authors.lastname: Li
authors.forename: Chih-Han
authors.initials: CH
authors.lastname: Chang
authors.forename: Kuan-Ting
authors.initials: KT
authors.lastname: Chen
mesh_terms: D000328:Adult; D001706:Biopsy; D015519:Bone Density; D016025:Bone Transplantation / Q000379:methods*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008443:Maxillary Sinus / Q000000981:diagnostic imaging* / Q000601:surgery*; D008875:Middle Aged; D019047:Phantoms, Imaging; D059546:Sinus Floor Augmentation / Q000379:methods*; D018709:Statistics, Nonparametric; D016896:Treatment Outcome; D055114:X-Ray Microtomography