This document discusses gingival inflammation and gingivitis. It begins by defining inflammation and describing the cardinal signs. It then outlines the stages of gingivitis from initial to established to advanced/periodontitis. Microorganisms attached to teeth secrete enzymes that damage tissues and widen junctional epithelium, allowing bacterial products to access connective tissue and activate immune cells. Studies showed that not practicing oral hygiene led to plaque buildup and gingivitis within 10-21 days. Gingivitis is characterized by redness, swelling, bleeding and is prevalent worldwide. The document discusses features, course, distribution and systemic influences of gingival inflammation.