Mechanisms of alveolar bone destruction in periodontitis

Fig. 3 summarizes the role of local factors in periodontal disease. Plaque and its associated bacteria, which populate the periodontal pocket, release lipopolysaccharide and other bacterial products to the sulcus, affecting both the immune cells in the connective tissue, as well as the osteoblasts. In the immune cells, these products induce local factor production, including IL-1α. IL-1β, IL-6, prostaglandin E2 and tumor necrosis factor α. These factors increase osteoclast formation and activation as well as inhibit osteoblast function. The bacterila products will also affect the osteoblasts directly, inhibiting their function and inducing factor production and release, eventually inducing pre-osteoclast differentiation and osteoblast activation.