Pericoronitis: a reappraisal of its clinical and microbiologic aspects.

Pericoronitis is an infectious disease of the operculum overlying an erupting or semi-impacted tooth. It manifests itself mainly in late adolescence and young adulthood and nearly always occurs around the lower third molar. The distinctive location, age, clinical picture, and link with predisposing factors warranted a reappraisal of pericoronitis and its etiology. Spirochetes and fusobacteria proved prevalent at all stages of the disease. The presence of these microbacteria may provide a clue as to the late appearance, particular location, and singular clinical picture of pericoronitis. The fact that spirochetes and fusobacteria are also found in acute necrotizing ulcerative gingivitis, and have been associated with alveolar osteitis, indicates a possible relationship between these disorders and pericoronitis.