Gingivitis ("inflammation of the gum tissue") is a non-destructive periodontal disease. The most common form of gingivitis, and the most common form of periodontal disease overall, is in response to bacterial biofilms (also called plaque) adherent to tooth surfaces, termed plaque-induced gingivitis. Gingivitis is reversible with good oral hygiene. However, in the absence of treatment, or if not controlled, gingivitis can progress to periodontitis, where the inflammation results in tissue destruction and alveolar bone resorption, which can ultimately lead to tooth loss.