title: Histological observations of a bilateral maxillary sinus floor elevation 6 and 12 months after grafting with osteogenic protein-1 device.
abstract: OBJECTIVE
  The purpose of this case study was to analyze the tissue formed in a maxillary sinus, 6 and 12 months after grafting with recombinant human osteogenic protein-1 (OP-1) linked to a collagen carrier of bovine origin.
  
  
  METHODS
  A 49-year-old woman referred for bilateral sinus floor elevation, was grafted with an OP-1 device. After 6 months, a biopsy was taken from one of the grafted areas. After 12 months, during implant placement, 5 biopsies were taken from the grafted area and the maxillary host bone. Biopsies were processed without decalcification for histological analyses.
  
  
  RESULTS
  The biopsy taken after 6 months contained newly formed bone, fibrotic tissue and device remnants. After 12 months, however, bone was absent from all biopsies which were taken from the grafted area, while particles of the collagen carrier were still abundant. Inflammatory cells were observed between remnants of the collagen carrier in the grafted area.
  
  
  CONCLUSIONS
  This study indicates that an onset of new bone formation, which was observed after 6 months, did not persist. 12 months after grafting no bone was present in the biopsies from the grafted area, while the collagen carrier had remained. Lack of mechanical loading, as a result of postponing implant placement from 6 to 12 months, may have resulted in resorption of the emerging bone which was present 6 months after grafting.
authors.affiliation: Department of Oral Cell Biology, ACTA, Vrije Universiteit, Amsterdam, The Netherlands.
authors.forename: H H
authors.initials: HH
authors.lastname: Groenveld
authors.forename: J P
authors.initials: JP
authors.lastname: van den Bergh
authors.forename: P
authors.initials: P
authors.lastname: Holzmann
authors.forename: C M
authors.initials: CM
authors.lastname: ten Bruggenkate
authors.forename: D B
authors.initials: DB
authors.lastname: Tuinzing
authors.forename: E H
authors.initials: EH
authors.lastname: Burger
mesh_terms: D001706:Biopsy; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins / Q000627:therapeutic use*; D016025:Bone Transplantation / Q000379:methods*; D003094:Collagen; D004337:Drug Carriers; D005260:Female; D006801:Humans; D007575:Jaw, Edentulous / Q000473:pathology / Q000601:surgery; D008437:Maxilla; D008443:Maxillary Sinus / Q000473:pathology* / Q000601:surgery; D008875:Middle Aged; D013516:Oral Surgical Procedures, Preprosthetic / Q000379:methods*; D011994:Recombinant Proteins / Q000627:therapeutic use; D013997:Time Factors; D016212:Transforming Growth Factor beta / Q000627:therapeutic use*
chemical_list: C525819:BMP7 protein, human; D055419:Bone Morphogenetic Protein 7; D019485:Bone Morphogenetic Proteins; D004337:Drug Carriers; D011994:Recombinant Proteins; D016212:Transforming Growth Factor beta; D003094:Collagen