Periodontal diseases(PD) are mainly associated with gram negative bacteria that initiate a series of events leading to the loss of periodontal attachment and alveolar bone surrounding teeth. Porphyromonas gingivalis (Pg) is considered to be one of the most important oral cavity infectious agents in adults patients. Pg is uncommon or found in low numbers in healthy children and don't know information in Juvenile Idiophatic Arthritis (J)IA patients.