Periodontal diseases include a group of infl ammatory diseases characterized by progressive destruction of the periodontium. Dental plaque is the initiator of periodontal disease, but disease severity and response to treatment are determined predominantly by host-based risk factors. Genetic disorders can modify the host defense mechanisms or infl uence the homeostasis of the periodontium during childhood, thus increasing patients’ susceptibility to periodontal disease. The periodontal manifestations of these disorders may persist into adulthood. When dealing with periodontal problems, particularly in children and adolescents, it is advisable to establish a differential diagnosis of periodontal disease due to systemic conditions. This...