“…However, bleeding is common to other periodontal diseases and while it is probable that pain is a frequent symptom of NUG patients who seek treatment for their problem, it is less clear whether pain is important among NUG cases identified in epidemiological studies. Hence, Grupe and Wilder (57), and Barnes et al (58) found that most NUG cases present only mild or no gingival pain. Additionally, in a comprehensive review of acute necrotizing ulcerative gingivitis, Johnson and Engel (59) warned against categorizing NUG too rigidly on the basis of gradation of symptoms, as we may fail to properly diagnose cases in subjects who do not present with all of the ‘typical’ signs and symptoms.…”