title: Healing patterns of critical size bony defects in rat following bone graft.
abstract: OBJECTIVE
  The aim of the present study was to evaluate the healing patterns of critical size calvarial bony defects treated with different bone substitutes and to compare them to an autogenous graft and an ungrafted control group.
  
  
  METHODS
  Thirty-six Sprague-Dawley rats (200-230 g) were used. A periosteal flap was raised and an 8 mm defect was trephined. Rats were divided into six groups and treated as follows: group 1 was treated with a deproteinized bovine xenograft (XO), group 2 was treated with a bovine xenograft and covered with a resorbable membrane (XOCM), defects in group 3 were filled with a decalcified freeze-dried bone allograft (DFDBA), group 4 was treated with a composite bone substitute made of bovine xenograft and collagen (XOC), group 5 was filled with autogenous bone (AUTO), and group 6 was left untreated (control). The animals were euthanized at 2 months.
  
  
  RESULTS
  Mean bone formation was 2.97 +/- 1.82 mm2 in group 5 (AUTO) followed by 2.93 +/- 1.93 mm2 in group 3 (DFDBA) and 2.25 +/- 1.94 mm2 in group 4 (XOC). Groups 1, 2, and 6 (XO, XOCM, and control, respectively) were not significantly different (p > 0.05) with a mean bone formation of 1.97 +/- 1.64, 1.87 +/- 1.07, and 1.85 +/- 1.04 mm2, respectively.
  
  
  CONCLUSIONS
  This work confirmed the superiority of autogenous bone when it comes to bone grafting. Nevertheless, some bone substitutes can improve bone formation when compared to the control. New bone substitutes with growth factors to improve their abilities to induce bone formation should be experimented.
authors.affiliation: Department of Periodontology, Faculty of Dentistry, Université Saint-Joseph, Beirut, Lebanon. nadim.mokbel@usj.edu.lb
authors.forename: N
authors.initials: N
authors.lastname: Mokbel
authors.forename: C
authors.initials: C
authors.lastname: Bou Serhal
authors.forename: G
authors.initials: G
authors.lastname: Matni
authors.forename: N
authors.initials: N
authors.lastname: Naaman
mesh_terms: D020341:Absorbable Implants / Q000145:classification; D000704:Analysis of Variance; D000818:Animals; D001672:Biocompatible Materials / Q000627:therapeutic use; D001857:Bone Matrix / Q000637:transplantation; D018786:Bone Substitutes / Q000145:classification / Q000627:therapeutic use*; D016025:Bone Transplantation / Q000379:methods*; D003094:Collagen / Q000627:therapeutic use; D003399:Craniotomy; D008903:Minerals / Q000627:therapeutic use; D016348:Osseointegration / Q000502:physiology*; D010012:Osteogenesis / Q000502:physiology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012886:Skull / Q000502:physiology / Q000601:surgery*; D014945:Wound Healing / Q000502:physiology
chemical_list: C106416:Bio-Gide; C077540:Bio-Oss; D001672:Biocompatible Materials; D018786:Bone Substitutes; D008903:Minerals; C403137:PepGen P-15; D003094:Collagen