[Biology of periodontal regeneration: a review and a hypothesis for future researches].

Since the end of the seventies several studies have been carried out about the possibility of regeneration of periodontal osseous defects. The results of such researches supported by histological tests allowed to establish which surgical techniques could yield periodontal regeneration in a predictable way. In spite of a quite large diffusion of these sugical techniques in the treatment of periodontal osseous defects, some biological aspects of periodontal regeneration are still unknown. The most important among them is the origin and the differentiation pathway of the synthetic cells that shall provide for the reconstruction of the deep periodontium. Particularly, the phenotypic pattern and the origin of cementoblasts are not clear. Our researches focused on pericytes, a mesenchyma-derived cell population with remarkable differentiation capacities which have a microvascular location. We considered the hypothesis that pericytes could play an important role in regeneration of the alveolar bone, of the cementum and of the periodontal ligament. Should pericytes be actually the precursors of osteoblatsts, fibroblasts and cementoblasts involved in periodontal regeneration, new therapies, such as cultivated cells reimplantation or the targeted use of growth factors could be feasible. Future researches shall verify these observations.