The potential coronal migration of periodontal ligament tissue following experimental regeneration.

The aim of the present study was to determine if the periodontal ligament cells can migrate onto curretted root surfaces following an experimental regeneration procedure. Buccal mucoperiosteal flaps were elevated in all three premolar regions in 5 mongrel dogs. The buccal bone was reduced to approximately 7 mm from its original level on 30 roots. Before the elevated flaps were replaced and sutured, Gore-Tex filters were adjusted to cover exposed root surfaces. No membranes were placed over 10 root surfaces, which served as controls. After 7 weeks of healing, the animals were sacrificed and all the roots were examined for histological evaluation of contralateral experimental and control teeth. With polychrome staining, the new periodontal ligament fibers of the curetted root surfaces were dyed methyl blue and the adjacent gingival collagen fibers were dyed red. On the experimental surface, coronal migration of periodontal ligament cells and connective tissue attachment were identified over long distances of curetted root surface. Periodontal ligament spaces were more prevalent in experimental sites than in control root surfaces. The results of the experiment suggest that the periodontal ligament cells actually migrated onto the curetted root surfaces when a periodontal space was created by physical barriers.