title: Role of collagen membrane in lateral onlay grafting with bovine hydroxyapatite incorporated with collagen matrix in dogs.
abstract: OBJECTIVE
  The objective of this study was to elucidate the role of collagen membranes (CMs) when used in conjunction with bovine hydroxyapatite particles incorporated with collagen matrix (BHC) for lateral onlay grafts in dogs.
  
  
  METHODS
  The first, second, and third premolars in the right maxilla of mongrel dogs (n=5) were extracted. After 2 months of healing, two BHC blocks (4 mm×4 mm×5 mm) were placed on the buccal ridge, one with and one without the coverage by a CM. The animals were sacrificed after 8 weeks for histometric analysis.
  
  
  RESULTS
  The collagen network of the membranes remained and served as a barrier. The quantity and quality of bone regeneration were all significantly greater in the membrane group than in the no-membrane group (P<0.05).
  
  
  CONCLUSIONS
  The use of barrier membranes in lateral onlay grafts leads to superior new bone formation and bone quality compared with bone graft alone.
authors.affiliation: Department of Periodontology, Research Institute for Periodontal Regeneration, Yonsei University College of Dentistry, Seoul, Korea.
authors.forename: Ui-Won
authors.initials: UW
authors.lastname: Jung
authors.forename: Jung-Seok
authors.initials: JS
authors.lastname: Lee
authors.forename: Geun
authors.initials: G
authors.lastname: Lee
authors.forename: In-Kyeong
authors.initials: IK
authors.lastname: Lee
authors.forename: Ji-Wan
authors.initials: JW
authors.lastname: Hwang
authors.forename: Min-Soo
authors.initials: MS
authors.lastname: Kim
authors.forename: Seong-Ho
authors.initials: SH
authors.lastname: Choi
authors.forename: Jung-Kiu
authors.initials: JK
authors.lastname: Chai
keywords: Alveolar ridge augmentation; Bone substitutes; Collagen; Guided tissue regeneration; Membranes