... proliferation, migration, and differ-entiation of the epithelial cells [2,12,18,19]. Following the surgical treatment of adult periodontitis, the epithelial regeneration of the periodontal attachment ... facilitate the direct clinical view of the defect [fig. 3-4]. A full-thickness flap was elevated and the granulation tissue was removed showing the true extension and depth of the infra-bone ... damaged site and on the other hand, it creates an environment with a rich content of HA, with all the advantages deriving from the phenomenon. The present study s clinic and radiologic results...