**Abstract**

Gingivitis and periodontitis are induced by numerous pathogenic microbiota hosted in the subgingival biofilm that first trigger the innate immune response. Innate immune response is part of a homeostatic system which is the first line defence and defines the host inherited resistance to infection. Both genetic and environmental factors are involved in variable individual susceptibility to inflammation of periodontal tissues. That is why, although more than 600 bacterial species have been detected in the periodontal plaque, the type of bacteria incriminated in the development of the inflammation is still unclear. Moreover, in the last decade gene polymorphisms have been largely recognised as important conditions associated with increased susceptibility to periodontal diseases. Manipulating the immune response by the development of drugs that inhibit adverse host reactions and promote beneficial effects might be of therapeutic or prophylactic importance. This work intends to assess the importance of Toll-like receptors as main effectors of the innate immune response in the triggering, maintenance and progression of periodontal inflammation, as well as of the involvement of synthetic molecules targeting TLR signalling pathways in treating periodontal diseases.

**Keywords:** innate immunity, toll-like receptors, periodontal inflammation, therapy
