title: Evaluation of a cell-permeable barrier for guided tissue regeneration combined with demineralized bone matrix.
abstract: OBJECTIVE
  To evaluate whether bone formation by guided tissue regeneration (GTR) and demineralized bone matrix (DBM) can be enhanced by the use of a cell-permeable Teflon barrier allowing the penetration of undifferentiated mesenchymal cells from the surrounding soft tissues.
  
  
  METHODS
  DBM was produced from the long bones of rats, and its bone-inductive properties were tested in three rats prior to the study by intramuscular implantation. Thirty, 4-month-old, male albino rats of the Wistar strain were used. Following surgical exposure of the mandibular ramus, a cell-permeable Teflon capsule, loosely packed with DBM, was placed with its opening facing the lateral surface of the ramus (test side). At the contralateral side, serving as control, a non-perforated (cell-occlusive) Teflon capsule, loosely packed with the same amount of DBM, was placed. After healing periods of 30, 60, and 120 days, groups of 10 animals were killed, and 40-70 microm thick undecalcified sections of the capsules were produced.
  
  
  RESULTS
  Computer-assisted planimetric measurements on the histological sections disclosed similar amounts of newly formed bone in both test and control capsules. After 4 months, the new bone in the control capsules occupied 45.0% of the cross-sectional area of the capsule, while it was 50.5% in the test capsules. This difference was not statistically significant (P<0.05).
  
  
  CONCLUSIONS
  Similar amounts of bone formed in cell-permeable and cell-occlusive capsules grafted with DBM, suggesting that invasion of undifferentiated mesenchymal cells from the surrounding soft tissues into the barrier-protected area is unnecessary for bone formation with GTR.
authors.affiliation: Department of Periodontology and Oral Gerontology, Royal Dental College, University of Aarhus, Denmark.
authors.forename: N
authors.initials: N
authors.lastname: Mardas
authors.forename: L
authors.initials: L
authors.lastname: Kostopoulos
authors.forename: A
authors.initials: A
authors.lastname: Stavropoulos
authors.forename: T
authors.initials: T
authors.lastname: Karring
mesh_terms: D000818:Animals; D001857:Bone Matrix / Q000637:transplantation*; D001861:Bone Regeneration / Q000502:physiology; D002465:Cell Movement; D048091:Guided Tissue Regeneration / Q000379:methods*; D008297:Male; D008334:Mandible / Q000166:cytology* / Q000601:surgery; D008567:Membranes, Artificial; D059630:Mesenchymal Stem Cells / Q000166:cytology*; D010012:Osteogenesis / Q000502:physiology; D010539:Permeability; D011138:Polytetrafluoroethylene; D011489:Protein Denaturation; D051381:Rats; D017208:Rats, Wistar; D014945:Wound Healing / Q000502:physiology
chemical_list: D008567:Membranes, Artificial; D011138:Polytetrafluoroethylene