Host modulation as a therapeutic strategy in the treatment of periodontal disease

Specific microorganisms initiate the immunoinflammatory processes that dest roy tissue in periodontitis. Recent work has demonstrated, in addition to b acterial control, that modulation of the host immunoinflammatory response i s also capable of controlling periodontitis. Matrix metalloproteinases (MMP s) destroy collagen and other matrix components, and the osteoclastic bone remodeling determines the periodontal bone response to a bacterial challeng e, Other components of the biology, including cytokines and prostanoids, re gulate MMPs and bone remodeling and are also involved in regulating the pro duction of defensive elements, such as antibody. Agents directed at blockin g MMPs or osteoclastic activity are effective in reducing periodontitis, Ag ents that inhibit prostaglandin E-2 and selective blockage of specific cyto kines have also been effective. Improved knowledge of bacterium-host intera ctions and of the processes leading to tissue destruction will help to iden tify targets for host modulation to reduce periodontitis in selected situat ions.