Classification of Periodontal Diseases

The recognition that diseases affecting the periodontal tissues can present in different forms has been a major advance in our understanding of the nature and prognosis of those disease in the last decade.

As a result, classification systems have been developed to reflect the variety of forms of gingivitis and periodontitis.

Consensus over the exact nomenclature to be used has not been reached between different countries; however, this information sheet provides an overview of how to classify periodontal diseases, with the aim of assisting you in recording an appropriate periodontal diagnosis on each patient's treatment record. 

Gingivitis is an inflammatory condition of the gingival tissues. Gingivitis lesions can be classified as:

  • chronic marginal gingivitis
  • acute necrotizing ulcerative gingivitis (ANUG)

Chronic marginal gingivitis is defined as inflammation of the marginal gingival tissues and is characterised by redness, swelling and bleeding. It is essentially a reversible condition. While gingivitis usually precedes the formation of periodontitis, this is in no way an inevitable consequence of gingivitis. 

Acute necrotizing ulcerative gingivitis (ANUG) is an inflammatory destructive gingival condition more commonly found in young adults, characterised by interproximal necrotic ulcers covered by debris, painful to touch and readily bleeding. ANUG seems to be related to poor plaque control with a pre- existing marginal gingivitis, smoking and emotional stress. 

Periodontitis is an inflammatory disease of the periodontium characterized by the presence of periodontal pockets and active bone resorption. Page and Schroeder (1982) define five distinct forms of periodontitis: 

  • prepubertal periodontitis
  • juvenile periodontitis 
  • rapidly progressive periodontitis
  • adult periodontitis 
  • acute necrotizing ulcerative gingivo-periodonitis

The most common type of these is the adult periodontitis. This is thought to commence after the age of 30 years, and may affect any or all teeth, with either vertical or horizontal patterns of bone loss. It rarely results in tooth loss, although some patients do appear to suffer rapid destruction of periodontal attachment at some stages. Acute exacerbations of the disease can superimpose on the chronic form, with the formation of pus, which can lead to a periodontal abscess. The majority of patients with adult periodontitis are relatively straightforward cases to treat for the general dental practitioner. The detection of other forms of periodontal diseases should be the responsibility of the general dental practitioner; however referral to a periodontist should be seriously considered for management of these conditions.

Prepubertal periodontitis is an extremely rare condition, leading to early exfoliation of the deciduous dentition, either with or without inflammation of the periodontal tissues. It is usually associated with systemic illness, such as Papillon-Lefevre Syndrome.

Juvenile periodontitis has been well documented, and is characterised by severe periodontal breakdown confined predominantly to the first permanent molars and/or incisors. The onset of the disease is thought to coincide with puberty, when it is highly active, but subsequently destruction may slow or spontaneously cease. The prevalence of the disease is estimated to be about one per thousand children. Clinically, the gingival tissues may appear completely normal, with very little plaque present. Therefore, diagnosis relies heavily on the use of a periodontal probe as a routine part of the dental examination and careful examination of any radiographs taken. Juvenile periodontitis is usually responsive to periodontal treatment; however, this may involve extensive root-planing, antibiotic therapy and surgical access.

Rapidly progressive periodontitis affects young adults under the age of 35 years. It causes widespread destruction of the periodontal tissues, affecting most teeth, and can result in early tooth loss. The disease undergoes active and inactive phases. During the active phase, the patient will often present with sore and swollen gingival tissues that bleed profusely on gentle probing. Increased mobility of teeth may also be noted. This active phase can last two to three weeks, before returning to an inactive phase.

If the patient attends during an inactive phase, there may be very few clinical cues to indicate the extent of underlying periodontal destruction that has occurred. Again, thorough periodontal probing and examination of radiographs is essential to detect this condition. This form of periodontitis usually requires aggressive treatment, with oral hygiene improvement, root-planing, antibiotic therapy and periodontal surgery being likely components of treatment. Early detection and referral for specialist care may give the patient the best prognosis.

The final category of periodontitis, acute necrotizing ulcerative gingivo-periodontitis, is usually associated with HIV-related periodontitis. It is often seen in the late stages of HIV infection, when the patient is severely immune-compromised. It appears to begin with typical signs of ANUG, but spreads rapidly to affect the underlying periodontal tissues, causing necrosis of bone and rapid exfoliation of teeth. Patients will often complain of a deepseated bone pain. 

This brief overview is a guide to forming a periodontal diagnosis for each of your patients. For more detailed information, you may like to refer to: 

1. Page RC, Schroeder HE. Periodontitis in Man and other animals. Karger: Basel, 1982. 
2. Williams DM, Hughes FJ, Odell EW, Farthing PM. Pathology of periodontal disease. Oxford University Press, 1992. 

or contact the Dental Practice Education Research Unit at the University of Adelaide.