A New Approach to Regeneration of Surgically Reduced Alveolar Ridges in Dogs: A Clinical and Histologic Study

Premolar teeth were extracted from dogs and the remaining alveolar bone was surgically reduced to produce Class III ridge defects. Following 2 months of healing, a new technique using allogeneic cortical columns to prop up the raised mucoperiosteal flaps and create space for developing tissue was employed to create space for regeneration of the ridges. In the control sites, the cortical columns alone were used to prop up the mucoperiosteal flap; whereas in the experimental sites, barrier membranes (expanded polytetrafluoroethylene or bone membranes) were interposed between the flaps and the projecting cortical columns. In alternate sites, decalcified allogeneic freeze-dried particulate bone was added to fill the voids between the cortical columns, the underlying host bone, and the membranes. Variations of the new approach that were based on the principles of guided tissue regeneration provided the most significant gains in ridge width, with a mean aggregate gain of 3.31 mm. Histologically, all variations of the basic technique were seen to have augmented the surgically reduced ridges. Osseous regeneration was observed only where the barrier membranes were used. The addition of particulate bone filler did not appear to offer any advantage. This new approach to ridge augmentation meets the requirements for alveolar ridge regeneration. Keywords: bone membranes, cortical columns, guided bone regeneration, regeneration requirements, ridge augmentation, ridge regeneration