Periodontal diseases affecting children and young adults.

: There is a group of periodontal diseases affecting children and young adults that is characterized by onset prior to age 35, often with a rapid rate of periodontal destruction. Although a wide variation in patterns of presentation exist, these diseases can be described under the broad categories of (a) early onset periodontitis (juvenile periodontitis), (b) necrotizing ulcerative gingivitis/periodontitis, (c) periodontitis associated with systemic diseases. A discussion of each of these categories is followed by two case reports which illustrate possible clinical presentations of these diseases.