13.4 The Periodontal Disease Process, the 2017 Classification & Plaque and Gingival Indices

13.4 The Periodontal Disease Process, the 2017 Classification & Plaque and Gingival Indices

Quick Answer: Competency 7.1.1 asks you to describe how periodontal disease develops and progresses, and 5.10.3 asks you to recognize healthy gingiva, gingivitis and periodontitis. Oral hygiene indices are recorded under 4.2.4 and 7.1.5.

• Healthy gingiva: coral pink, firm, stippled and knife-edged, with a 1 to 3 mm sulcus and no bleeding.
• Gingivitis: red, swollen, bleeding gingiva with no attachment loss; it is reversible.
• Periodontitis: irreversible loss of connective tissue attachment and bone.

The 2017 AAP/EFP classification stages periodontitis I to IV (severity and complexity) and grades it A to C (rate of progression). Necrotizing gingivitis presents with painful, cratered, bleeding papillae and a fetid odour. It is managed with gentle debridement, careful brushing and warm rinses, while the risk factors are addressed. In the Silness and Löe Plaque Index, a score of 3 means an abundance of soft deposits on the tooth and gingival margin.

1. Healthy Gingiva versus Gingivitis

2. How Periodontal Disease Develops (7.1.1)

1. Biofilm accumulates at and below the gingival margin. If it is not removed, the community shifts from mostly Gram-positive aerobes towards Gram-negative anaerobes and spirochetes (section 13.3).
2. Gingivitis develops within days to weeks. Vessels dilate, fluid and white blood cells move into the tissue, and the gingiva becomes red, swollen and bleeds easily. Gingivitis is reversible with good plaque control.
3. In a susceptible host, the host's own inflammatory response (cytokines, prostaglandins, enzymes; section 13.3) breaks down the connective tissue attachment and alveolar bone. The junctional epithelium migrates apically and a true periodontal pocket forms. This is periodontitis: the attachment loss is permanent.
4. Progression is usually slow and episodic, with periods of activity and rest. As bone support is lost, teeth may drift, become mobile and finally be lost.

Factors affecting development and progression:

• Local: calculus, overhanging or open restorations, crowding, orthodontic appliances, mouth breathing, food impaction and partial dentures that trap plaque.
• Systemic risk factors and modifiers: smoking (the most important modifiable risk factor), diabetes (especially if poorly controlled), stress, genetics, hormonal changes (puberty, pregnancy), medications (drug-induced enlargement, xerostomia), immunosuppression and poor nutrition.

3. The 2017 AAP/EFP Classification of Periodontal and Peri-Implant Diseases

The 2017 World Workshop classification groups conditions into:

• Periodontal health and gingival diseases: periodontal health; dental biofilm-induced gingivitis (including gingivitis modified by systemic or local factors, and drug-influenced gingival enlargement); and non-biofilm-induced gingival diseases (for example, viral, fungal or immune conditions).
• Periodontitis, classified by stage and grade.
• Necrotizing periodontal diseases: necrotizing gingivitis, necrotizing periodontitis and necrotizing stomatitis.
• Periodontitis as a manifestation of systemic disease.
• Other conditions affecting the periodontium: periodontal abscesses, endodontic-periodontal lesions, mucogingival deformities and traumatic occlusal forces.
• Peri-implant health, peri-implant mucositis and peri-implantitis (section 12.3).

Staging (severity and complexity)

Extent: localized (fewer than 30% of teeth), generalized (30% or more), or a molar-incisor pattern.

Grading (rate of progression and risk)

A diagnosis might read "Generalized periodontitis, Stage III, Grade B". The dentist (or hygienist, within scope) makes the diagnosis. The assistant records accurate data and recognizes the signs.

4. Necrotizing Periodontal Diseases

Necrotizing gingivitis (formerly acute necrotizing ulcerative gingivitis):

• Signs: sudden onset of painful, punched-out (cratered) interdental papillae, often covered with a grey pseudomembrane, spontaneous bleeding and a fetid odour. Fever, malaise and enlarged lymph nodes may be present.
• Risk factors: psychological stress, smoking, poor oral hygiene, lack of sleep, malnutrition and immunosuppression (including HIV infection). Typical patients are young adults under stress, such as students during exams.
• Necrotizing periodontitis adds attachment and bone loss. Necrotizing stomatitis spreads beyond the gingiva.
• Management:
  • gentle debridement (often with an ultrasonic scaler under local or topical anesthesia)
  • careful brushing with a soft brush
  • warm water or saline rinses (an antimicrobial rinse may be added for a short time)
  • rest, fluids and nutrition, and stopping smoking
  • follow-up visits
  • systemic antibiotics (for example, metronidazole) only when there are systemic signs, as prescribed by the dentist.

5. Plaque, Gingival and Oral Hygiene Indices (4.2.4, 7.1.5)

Indices give a number that can be recorded, compared over time and used to motivate the patient. Record the index used, the date and the score.

Silness and Löe Plaque Index (PlI)

Löe and Silness Gingival Index (GI)

• 0: normal gingiva.
• 1: mild inflammation: slight change in colour, slight oedema, no bleeding on probing.
• 2: moderate inflammation: redness, oedema, glazing, bleeding on probing.
• 3: severe inflammation: marked redness and oedema, ulceration, tendency to spontaneous bleeding.

Simplified Oral Hygiene Index (OHI-S, Greene and Vermillion)

• Six index surfaces: the buccal of 16 and 26, the labial of 11 and 31, and the lingual of 36 and 46.
• Debris (DI-S) and calculus (CI-S) are each scored 0 to 3 per surface, totalled and divided by the number of surfaces scored. OHI-S = DI-S + CI-S (range 0 to 6).
• Interpretation: good 0.0–1.2; fair 1.3–3.0; poor 3.1–6.0.
• Worked example: debris scores of 1, 1, 0, 2, 1, 1 give a DI-S of 6 ÷ 6 = 1.0. Calculus scores of 0, 0, 0, 1, 1, 0 give a CI-S of 2 ÷ 6 = 0.33. The OHI-S is 1.33, which is fair.

Bleeding and screening indices

• Bleeding on probing (%) = sites that bleed ÷ sites probed × 100. It is a quick measure of inflammation to track at each visit.
• Periodontal Screening and Recording (PSR): each sextant is probed with a ball-ended probe whose coloured band runs from 3.5 to 5.5 mm, and the highest code is recorded:
  • 0 band fully visible, no calculus, no bleeding
  • 1 bleeding
  • 2 calculus or defective margins
  • 3 band partly visible (3.5–5.5 mm)
  • 4 band disappears (more than 5.5 mm)
  • an asterisk (*) flags furcation involvement, mobility, mucogingival problems or recession of 3.5 mm or more. A code 3 calls for full periodontal charting of that sextant (or of the whole mouth if two or more sextants score 3), and a code 4 calls for full-mouth charting (section 7.2).