Pericoronitis Pericoronitis is a localized, acute infection surrounding an erupting tooth It is usually associated with erupting molars in the adolescent patient, although a mild form may be associated with the eruption of the first permanent molar ( Table 117.1 ) Symptoms usually include pain distal to the last erupted tooth in the dental arch, along with erythema and edema localized to the gingiva in the retromolar area Localized, painful lymphadenopathy, trismus, and dysphagia may accompany these symptoms Children may occasionally have accompanying fever It is usual to see or palpate the cusps of the erupting tooth The patient may complain of an inability to completely close his or her mouth because of the edematous gingiva Exudate may be expressed from beneath the infected flap of tissue Rarely, pain may be referred to the ear, though no pathology will be identified on otologic examination Acute Necrotizing Ulcerative Gingivitis, Trench Mouth Acute necrotizing ulcerative gingivitis (ANUG), also known as trench mouth, results from increases in fusiform bacillus and Borrelia vincentii, a spirochete, which usually coexist in a symbiotic relationship with other oral flora Immunocompromised patients are at increased risk for this condition Other associated risk factors include: emotional stress, malnutrition, severe dehydration, poor oral hygiene, and infectious mononucleosis TABLE 117.1 ERUPTION SCHEDULE FOR SPECIFIC TEETH