Any local factors that stimulate gingivitis longer and more severely, such as tartar and soft tartar buildup, poor oral hygiene, food impaction, microbial action, and poor restorations, can cause periodontitis in the presence of decreased body resistance or enhanced pathogenic factors. In addition, systemic factors sometimes play a contributing role in the development of periodontitis. These systemic factors reduce the resistance of the periodontal support tissues to local factors and the ability to repair them, thus turning local factors that could not cause pathology into factors that can cause disease. Systemic systemic diseases can contribute to the development of periodontal disease and its increased severity.