Aggressive periodontal disease is an oral health mystery. Our current understanding of this disease is that specific bacteria invade the oral cavity and the host reacts with an inflammatory response leading to mass destruction of the alveolar bone. Aggressive periodontal disease is typically observed in a population under the age of 30 and occurs so rapidly that it is difficult to treat. Unfortunately, the consequence of this disease frequently involves tooth extractions. As a result, the aftermath is chewing disability and damage to self-esteem due to an altered self-image. Furthermore, patients are encumbered by frequent dental appointments which have an economic impact in regards to both personal financial strain and absent days in the workplace. Aggressive periodontal disease has a tremendous effect on patients' overall quality of life and needs to be investigated more extensively in order to develop methods for earlier definitive diagnosis and effective treatments. One of the mysteries of aggressive periodontal disease is the relatively nominal amount of plaque present on the tooth surface in relation to the large amount of bone loss. There seems to be a hidden factor that lies between the response by the patient's immune system and the bacterial threat that is present. A better mechanistic understanding of this disease is essential to provide meaningful care and better outcomes for patients. Schlagwörter: bone, bone loss, gingival health, juvenile periodontitis, plaque