title: Effect of GBR in combination with deproteinized bovine bone mineral and/or enamel matrix proteins on the healing of critical-size defects.
abstract: OBJECTIVE
  To evaluate the effect of guided bone regeneration (GBR) in combination with or without deproteinized bovine bone mineral (DBBM) and/or an enamel matrix derivative (EMD) on the healing of critical-size calvarial defects.
  
  
  METHODS
  Forty rats were used. In all animals, a standardized critical-size calvarial defect was created surgically. The animals were randomly allocated into 4 groups of 10 animals each. Group A: One calvarial defect was left untreated, while the galeal and the cerebral aspect of the contralateral defect were covered with a bioresorbable membrane (GBR). Group B: One calvarial defect was filled with EMD, while the contralateral defect was treated with GBR and EMD. Group C: One defect was filled with DBBM, while the contralateral defect was treated with combination of GBR and DBBM. Group D: One defect was filled with DBBM combined with EMD, while the contralateral defect was treated with combination of GBR, DBBM and EMD. The healing period was 4 months. Five specimens from each group were macerated and the length, the width and the vertical dimension (thickness) of the remaining defect were evaluated by a stereomicroscope. The remaining specimens in each group were analyzed histologically.
  
  
  RESULTS
  The defects of the macerated specimens that were left untreated or were treated only by EMD, DBBM and combination of EMD and DBBM did not present predictably complete healing of the defects. All the defects where GBR was applied alone or combined with DBBM and/or EMD presented always complete healing (P<0.05). The combined use of GBR with EMD and/or DBBM did not offer any significant advantage above GBR alone in terms of healing of the length and the width of the defect. However, the vertical dimension of the defect was significantly higher (P<0.05) in the GBR-treated specimens of Groups C and D. The histological analysis supported these findings.
  
  
  CONCLUSIONS
  The predictability of bone formation in critical-size defects depends mainly on the presence or absence of barrier membranes (GBR). The combined use with deproteinized bovine bone mineral and/or enamel matrix proteins did not significantly enhance the potential for complete healing provided by the GBR procedure.
authors.affiliation: Department of Periodontology, Eastman Dental Institute, University College London, UK. N.Donos@eastman.ucl.ac.uk
authors.forename: Nikolaos
authors.initials: N
authors.lastname: Donos
authors.forename: Niklaus P
authors.initials: NP
authors.lastname: Lang
authors.forename: Ioannis K
authors.initials: IK
authors.lastname: Karoussis
authors.forename: Dieter
authors.initials: D
authors.lastname: Bosshardt
authors.forename: Maurizio
authors.initials: M
authors.lastname: Tonetti
authors.forename: Lambros
authors.initials: L
authors.lastname: Kostopoulos
mesh_terms: D000818:Animals; D001672:Biocompatible Materials; D001857:Bone Matrix / Q000637:transplantation; D001861:Bone Regeneration; D018786:Bone Substitutes; D016025:Bone Transplantation / Q000379:methods; D002417:Cattle; D003094:Collagen; D003746:Dental Enamel Proteins; D048091:Guided Tissue Regeneration / Q000379:methods*; D008297:Male; D008567:Membranes, Artificial; D008903:Minerals; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D015203:Reproducibility of Results; D012886:Skull / Q000601:surgery; D018709:Statistics, Nonparametric
chemical_list: C106416:Bio-Gide; C077540:Bio-Oss; D001672:Biocompatible Materials; D018786:Bone Substitutes; D003746:Dental Enamel Proteins; D008567:Membranes, Artificial; D008903:Minerals; C109069:enamel matrix proteins; D003094:Collagen