Oral tissues are constantly exposed to damage from the mechanical efort of eating and from the invasion of foreign microorganisms such as bacteria, fungi, and virus. In healthy oral tissues, there is a balance between symbiotic bacteria and cells from the innate immune system, mainly neutrophils. When this balance is broken, inlammation appears and more immune cells are recruited to the gingiva. Neutrophils form a barrier against dysbiotic bacteria. However, when neutrophils are insuicient, bacteria thrive causing periodontitis, a chronic inlammatory disease that destroys the tooth-supporting tissues or periodontium. Damage of periodontal tissues leads to tooth loss, and in severe cases, it can also afect systemic health by increasing a person's risk for atherosclerosis, rheumatoid arthritis, diabetes, and even cancer. The mechanisms neutrophil employ to keep a balance with bacteria in order to maintain healthy oral tissues is the focus of this chapter. We discuss how neutrophil antimicrobial functions keep bacteria at check and how some dysbiotic bacteria block neutrophils to promote an inlammatory state. Also, novel therapeutic approaches for periodontitis are discussed.