Alveolar ridge regeneration in two-wall-damaged extraction sockets of an in vivo experimental model

Aim: To determine the healing outcome following grafting with deproteinized porcine bone mineral (DPBM) with or without collagen membrane coverage in two-wall (both buccal and lingual)-damaged extraction sockets. Materials and methods: Distal roots of three mandibular premolars in six beagle dogs were extracted, and the whole buccal and lingual bony walls were surgically removed. Three treatment protocols were then applied according to the following group allocation: no graft (None), grafting DPBM (BG), and grafting DPBM with coverage by a collagen membrane (BG + M). Two observational periods (2 and 8 weeks) were used with the split-mouth design, and quantitative and qualitative analyses were performed by microcomputed tomography and histology. Results: The dimensions of the alveolar ridge at both grafted sites (BG and BG + M) remained similar to those of the pristine ridge in the histologic and radiographic analyses, whereas the ungrafted sites (None) collapsed both vertically and horizontally. Both grafting protocols produced substantial bony regeneration, but the addition of a covering membrane enhanced the proportion of mineralized tissue within the augmented area, and the BG + M group also showed a significantly larger area of regenerated ridge than the None group (p <.05). Conclusions: Bone grafting with collagen membrane can maintain the alveolar ridge dimensions with substantial bone regeneration in a two-wall-damaged extraction socket.