New Classification of Periodontal Diseases

Unquestionably classification of periodontal diseases is very complex and certainly not easy. It is, therefore, understandable that besides the numerous classifications which have been applied so far, or are still in use, the latest classification is only a temporary solution to this problem. The first generally acknowledged classification appeared in 1966 in Ann Arbor (Michigan, USA) during the first Workshop, at which there was almost no discussion on classification of diseases, apart from their classification into “Gingivitis” and “Periodontitis”. The reason for this being that at that time classifications were based more on the pathomorphological. on the basis of clinical appearance and course of disease, while knowledge on the etiology and pathogenesis were deficient. However, a dynamic pathobiological view, based on aetiology and microbiology, changed the concept of classification at that time, mainly due to the authors Page and Schroeder in 1982. Classification of Periodontal Diseases Third World Workshop of the American Academy of Periodontology (AAP) held in 1989 in Princetown (California, USA) for the first time a detailed classification was presented of periodontal diseases and conditions. During the following years classification of periodontal diseases was corrected and simplified in America and in Europe. At the beginning of November, 1999 the Workshop for Classification of Periodontal Diseases and Conditions was held which for the first time offered the opportunity of agreeing on a globally accepted and scientifically founded classification. The aim of this study was to present the latest classification of periodontal diseases and to recommend it to epidemiologists, scientists and clinicians, working in the field of periodontology.

CLASSIFICATION OF PERIODONTAL DISEASES

According to the 1999 International Workshop for Classification of Periodontal Diseases and Conditions, Following intensive discussions based on a comprehensive review of literature a decision was made on a new classification of the diseases. The following classification of periodontal diseases was proposed:

1. Gingival diseases (G)

2. Chronic periodontitis (CP)

3. Aggressive periodontitis (AP)

4. Periodontitis as a manifestation of systemicdiseases (PS)

5. Necrotizing periodontal diseases (NP)

6. Periodontal abscesses

7. Periodontitis with endodontic lesion

8. Developed and acquired deformations and conditions

I. Gingival diseases (G)

A. Gingival diseases caused by plaque

1. Gingivitis exclusively caused by plaque

A. With no local modifying factors

B. with local modifying factors (see VIIIA)

2. Gingival diseases modified with systemic factors

A. connected with hormonal influences

1) Gingivitis connected with puberty

2) Gingivitis connected with the menstrual cycle

3) Connected with pregnancy

a) Gingivitis in pregnancy

b) Pyogenic granuloma

4) Gingivitis connected with diabetes mellitus

B. connected with blood disease

1) Gingivitis connected with leukaemia

2) Other diseases

3. Gingival diseases modified by application of medications           

a. gingival diseases caused by medications

1) Gingival growths caused by medications

2) Gingivitis caused by medications

a) Gingivitis connected with oral contraceptives

b) Other medications

4. Gingival diseases caused by malnutrition

A. gingivitis due to lack of vitamin C

B. others

B. Gingival lesions not induced by plaque

1. Gingival diseases of specific bacterial etiology

A. lesions connected with Neisseria gonorrhoeae

B. lesions connected with Treponema pallidum

C. lesions connected with streptococci

D. others

2. Gingival diseases of viral etiology

A. infection with the herpes virus

1) Primary herpetic gingivostomatitis

2) Recurring oral herpes

3) varicella zoster infection

B. others

3. Gingival diseases of fungal etiology

A. infection with candida

1) Generalized gingival candidiasis

B. linear gingival erythema

C. histoplasmosis

D. others

4. Gingival diseases of genetic etiology

A. inherited fibromatosis of the gingiva

B. others

5. Systemic diseases which manifest on theGingiva

A. changed mucous membrane

1) Lichen planus

2) Pemphigoid

3) Pemphigus vulgaris

4) Erythema multiformis

5) Lupus erythematosus

6) Caused by medications

7) Others

B. allergic reactions

1) Material in restorative dentistry

a) Mercury

b) Nickel

c) Acrylic

d) Others

2) Reaction to:

a) Toothpaste

b) Mouthwashes

c) Additives in chewing gum

d) Nutritive substitutes

3) Others

6. Traumatic lesions (iatrogenic, accidents)

a.      chemical

b.      physical

c.       thermal

7. Reaction to foreign bodies

8. Not otherwise defined

II. Chronic periodontitis (CP)

A.      Localized

B.      Generalized

III. Aggressive periodontitis (AP)

A.      Localized

B.      Generalized

IV. Periodontitis as a manifestation of systemic diseases (NP)

1. Connected with blood diseases

a.      Acquired neutropenia

b.      Leukemia

c.       Others

B. Connected with genetic disorders

1. Family or cyclic neutropenia

2. Down’s syndrome

3. Leucocyte adhesive deficiency syndrome

4. Papillon-Lefevre syndrome

5. Chediak-Higashi syndrome

            6. Histiocytosis or eosinophilic granuloma syndrome

7. Glycogen storage syndrome

8. Infantile genetic agranulocytosis

9. Cohen’s syndrome

10. Ehlers-Danlos syndrome, type IV and VIII AD

11. Hypophosphatasia

12. Others

C. Not otherwise defined

V. Necrotizing periodontal diseases

A. Necrotizing ulcerous gingivitis /NUG)

B. Necrotizing ulcerous periodontitis (NUP)

VI. Periodontal abscesses

A. Gingival abscess

B. Periodontal abscess

C. Pericoronal abscess

VII. Periodontitis with endodontal lesions

A. Combined paro-endo lesion

VIII. Developmental and acquired deformation and conditions

A. Localised dental factors which encourage Plaque, caused by gingivitis / periodontitis

1. Anatomy of the teeth

2. Reconstruction of teeth/effect of the device

3. Fractured root

4. Resorption of roots and (cement pearls)

B. Mucogingival deformities and relations in the tooth vicinity

1. Recession

a. facially and orally

b. approximally

2. Lack of gingival keratinization

3. Shortened gingival attachment

4. Localisation of the tongue or lip frenulum

5. Gingival enlargement

a. Pseudo-pockets

b. Irregular development of the gingival edge

c. Excessive gingival presentation

d. Gingival enlargement

6. Abnormal staining

C. Changed mucous membrane on an edentulous ridge

1. Loss of vertical or horizontal bone dimension

2. Loss of gingiva, i.e. keratinized tissue

3. Gingival growths, i.e. of soft tissue

4. Abnormal localization of the tongue or lip frenulum

5. Reduced vestibulum depth

6. Abnormal staining

D. Occlusal trauma

1. Primary occlusal trauma

2. Secondary occlusal trauma

When the new classification is analyzed essential differences can be seen compared to the classification of 1989, which was used in previous years

(7). Contrary to the former classification, which did not include gingival diseases, the new classification classifies them in two groups: gingival diseases caused by plaque and those not caused by plaque The term “adult periodontitis (AP) has been changed to “chronic periodontitis (CP)”. The term AP was the cause of constant dilemma for clinicians, due to the fact that this type of periodontitis can also be found in adolescents. Consequently, the term “adult” was completely unsuitable with regard to the age of such subjects. The term CP, therefore, is more suitable as it is not limited by the age of the patient. Some of the characteristics of CP are:

•        Generally occurs in adults but can also occur in children and adolescents.

•        Periodontal destruction is clearly related to local irritating factors.

•        Frequent presence of sub-gingival plaque.

•        Microbial composition of the plaque varies.

•        Usually of slow progression, with possible active recurrence.

•        May be further classified on the basis of distribution and degree of severity.

•        May be associated with a local specific factor, particularly iatrogenic irritation.

•        May be modified or associated with systemic diseases (e.g. diabetes mellitus or HIV-infection).

•        May be modified with risk factors, e.g. tobacco smoking and emotional stress. With regard to involvement CP is divided into

“localized” when it involves less than 30%, and

“generalized” when it involves more than 30% of the affected area.

 Based on the degree of severity and loss of attachment (CAL), CP may be

·         Mild (CAL = 1-2mm)

·         Moderate (CAL = 3-4mm)

·         Advanced (CAL > 5mm) (10).

The term “Early-onset periodontitis”, which was used earlier (AAP 1989 and the European Classification1993) and which included different periodontal diseases in young people (prepuberty, juvenile, rapid progressive periodontitis), has been changed to “aggressive periodontitis” Some of the characteristics of AP are:

·         Apart from periodontitis patients are clinically healthy.

·         Tissue destruction is rapidly progressive.

·         Significant frequency in the family.

·         Disparity between the amount of the bacterial deposit and the extent of tissue destruction.

·         Increased number of bacteria of the genus Actinobacillus Actinomycetemcomitans, and in   some populations P. gingivalisa.

•        Abnormal phagocytic function.

•        Hyper reactive phenotype macrophage with increased PGE2 and ILß production.

•        Tissue destruction may be self-limiting. AP can be localized and generalized. The localized form commences during puberty, involving first the molars and the central incisors, and has a high antibody titer against the verified bacteria. The generalized form occurs in patients younger than 30 years, with loss of attachment of at least three teeth, apart from the first molars and central incisors. There is acute exacerbation and the antibody titer against the verified bacteria is low. The new classification no longer contains “refractory periodontitis”, and ulceronecrotic periodontitis has been changed by the term “Necrotizing Periodontal Diseases”. Other categories have also been added, “Periodontal Abscesses”, “Periodontitis with Endodontal Lesions” and “Developmental and Acquired Deformations and Conditions

References:

Acta Stomatol Croat, Vol. 35, br. 1, 2001.

1999 International Workshop for Classification of Periodontal Diseases and Conditions, 30. 10. 1999 to 2. 11. 1999.