Role of collagen membrane in lateral onlay grafting with bovine hydroxyapatite incorporated with collagen matrix in dogs.

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. 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. 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). The use of barrier membranes in lateral onlay grafts leads to superior new bone formation and bone quality compared with bone graft alone.