title: Maxillary sinus augmentation with porous titanium granules: a microcomputed tomography and histologic evaluation of human biopsy specimens.
abstract: OBJECTIVE
  The aim of this study was to assess bone ingrowth into porous titanium granules used for maxillary sinus augmentation.
  
  
  METHODS
  Eighteen biopsy specimens from 17 patients participating in a clinical trial on sinus augmentation using porous titanium granules (PTG) were received in the laboratory. The specimens (trephine cores of 4.5 mm) were obtained 6 months after PTG placement. After being embedded in methacrylate, the samples were scanned in a microcomputed tomography (micro-CT) scanner. Specimens were then cut along the long axis and central slices were ground to 70 μm before staining with hematoxylin and eosin.
  
  
  RESULTS
  The micro-CT analysis demonstrated an average bone fill of 19% (standard deviation [SD] 5.8%), whereas the graft material occupied 22.7% (SD 4.7%). The volume of newly formed bone decreased with the distance from the residual bone of the sinus floor. Two-dimensional histomorphometric analysis demonstrated a mean area of new bone of 16.1% (SD 9.4%). The PTG alone occupied 25.9% of the total mean area (SD 6.1%). The newly formed bone consisted mainly of woven bone growing in close contact with the granules and bridging the intergranular space. The remaining area was occupied predominantly by nonmineralized connective tissue. There were no signs of inflammation in any of the biopsy specimens.
  
  
  CONCLUSIONS
  After 6 months, new bone had formed at a similar rate and quality as has been reported for other well-recognized bone graft substitutes. The new bone formed in close contact with the PTG, suggesting that the material is osteoconductive.
authors.affiliation: Department of Biomaterials, Institute of Clinical Odontology, University of Oslo, Oslo, Norway. anderver@odont.uio.no
authors.forename: Anders
authors.initials: A
authors.lastname: Verket
authors.forename: Ståle Petter
authors.initials: SP
authors.lastname: Lyngstadaas
authors.forename: Lars
authors.initials: L
authors.lastname: Rasmusson
authors.forename: Hans Reidar
authors.initials: HR
authors.lastname: Haanæs
authors.forename: Mats
authors.initials: M
authors.lastname: Wallström
authors.forename: Gert
authors.initials: G
authors.lastname: Wall
authors.forename: Johan Caspar
authors.initials: JC
authors.lastname: Wohlfahrt
mesh_terms: D000540:Alveolar Ridge Augmentation / Q000379:methods*; D001706:Biopsy; D003238:Connective Tissue / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male; D008443:Maxillary Sinus; D008875:Middle Aged; D016348:Osseointegration / Q000502:physiology*; D016062:Porosity; D014025:Titanium / Q000627:therapeutic use*; D055114:X-Ray Microtomography
chemical_list: D014025:Titanium