title: Three-dimensional analysis of bone formation after maxillary sinus augmentation by means of microcomputed tomography: a pilot study.
abstract: OBJECTIVE
  Although many studies have analyzed the suitability of different grafting materials for maxillary sinus augmentation by means of histomorphometry in conventional histologic strains, the three-dimensional (3D) structure and remodeling of these grafts after healing beneath the sinus membrane remain unclear. The aim of the present study was to determine whether microcomputed tomography is a suitable method to evaluate the 3D structure and remodeling of grafts after sinus floor augmentation.
  
  
  METHODS
  Sinus floor augmentation was performed in five patients using autogenous bone (AB) alone, AB and beta-tricalcium phosphate (b-TCP, Cerasorb), AB and b TCP/hydroxyapatite (HA) (BoneCeramic), AB and calcium carbonate (Algipore), and AB and HA (PepGen). Specimens from the grafted sites were harvested by means of a trephine bur 5 to 16 months after maxillary sinus augmentation. Microcomputed tomography of these specimens was performed with a nominal isotropic resolution of 6 x 6 x 6 μm² voxel size. After segmentation, 3D images were reconstructed, and the distribution of bone and substitute material was evaluated by means of volumetric and density measurements.
  
  
  RESULTS
  In all images, both bone and substitute material could clearly be identified. The connectivity of trabeculae surrounding the substitute material was visible in the 3D reconstructions. Volumetric evaluation such as total bone volume, volume of substitute material, and trabecular thickness and spacing revealed differences between the different grafting materials.
  
  
  CONCLUSIONS
  Microcomputed tomography is a promising method to evaluate the 3D structure of grafts after sinus floor augmentation with autogenous bone and bone substitute materials.
authors.affiliation: Clinic for Oral Surgery, Radiology, and Oral Medicine, Department of Oral Surgery, Hebelstrasse 3, Basel, Switzerland. dr.kuehl@email.de
authors.forename: Sebastian
authors.initials: S
authors.lastname: Kühl
authors.forename: Hermann
authors.initials: H
authors.lastname: Götz
authors.forename: Torsten
authors.initials: T
authors.lastname: Hansen
authors.forename: Matthias
authors.initials: M
authors.lastname: Kreisler
authors.forename: Alexandra
authors.initials: A
authors.lastname: Behneke
authors.forename: Uli
authors.initials: U
authors.lastname: Heil
authors.forename: Heinz
authors.initials: H
authors.lastname: Duschner
authors.forename: Berndt
authors.initials: B
authors.lastname: d'Hoedt
mesh_terms: D000328:Adult; D015519:Bone Density; D001861:Bone Regeneration; D018786:Bone Substitutes; D016025:Bone Transplantation; D002130:Calcium Phosphates; D017886:Durapatite; D005260:Female; D006801:Humans; D008297:Male; D008443:Maxillary Sinus / Q000000981:diagnostic imaging* / Q000601:surgery*; D008875:Middle Aged; D013516:Oral Surgical Procedures, Preprosthetic / Q000379:methods; D010865:Pilot Projects; D055114:X-Ray Microtomography
chemical_list: D018786:Bone Substitutes; D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate; D017886:Durapatite