Periodontal disease

In dealing with a specialty subject that involves the mouth, jaws and face it is obvious that aspects of pathology and treatment of the teeth that interlink or provide context with oral and maxillofacial surgery is required. This is the point of the entire section on restorative dentistry where another specialist subject is very briefly touched upon to give context and some detail in relevant subsections; periodontal disease being one such condition.

Whilst gingivitis is inflammation of the gingival tissues around teeth, periodontitis is inflammation of the periodontium including the periodontal ligament and alveolar bone. Often, gingivitis is considered to be the reversible phase of periodontal disease characterised by bleeding gingivae, redness and swelling, often associated with poor oral hygiene. Pain is not usually a symptom. Probing depths exceeding 3 mm may be present due to false pocketing.  Periodontitis is not reversible, and alongside the symptoms of gingivitis, there may also be gingival recession, pain and halitosis. Teeth may become mobile or lost due to damage to the surrounding bone, periodontal ligament and gingivae.

The presence of a plaque biofilm leads to the host initiating an inflammatory response within the gingival tissues. Whilst this response is intended to be protective, ‘bystander damage’ can also result in damage to the local tissues. The bacterial biofilm composition throughout the mouth is varied depending on the site. Biofilms on the teeth for example in the occlusal fissures are mainly Gram-positive facultative anaerobes, whereas those in periodontal pockets are mainly obligate anaerobic Gram-negative rods and cocci.

Whilst the current classification for periodontal diseases used was introduced in 1999, in 2018 a new global classification system for periodontal health, diseases and conditions was announced. The new classification for periodontitis includes stages I to IV (from initial to severe periodontitis with potential for loss of the dentition) and grades A to C (from slow to rapid rate of progression), alongside extent and distribution of disease (localised, generalised, molar-incisor distribution).

The management and treatment of periodontal disease requires a significant effort by patients at home. Any risk factors, such as diabetes and smoking, need to be identified. A plaque-free score, marginal bleeding and basic periodontal examination should be recorded at the examination stage. This allows for assessment of plaque control and inflammation and acts as a guide as to what further investigations or treatment may be required.

The most recent British Society of Periodontology guidelines (2016) stipulate that the appropriate way to record a basic periodontal examination is through division of the dentition into six sextants and the highest score for each sextant recorded. Third molars are not included unless 1st and/or 2nd molars are absent. If a sextant contains one or no teeth, it does not qualify for recording. The WHO basic periodontal examination probe with a ball end of 0.5 mm diameter and a black band from3.5 mm to 5.5 mm is recommended, alongside a 20 to 25 g light probing force.

The guidelines for the scoring codes and recommended actions are summarised in Table 1.

Table 1 Scoring codes, findings and recommended actions in basic periodontal examination

Score Observations Recommended actions
0 Pockets < 3.5mm, no calculus/overhangs, no bleeding on probing (black band entirely visible) No need for periodontal treatment
1 Pockets <3.5mm, no calculus/overhangs, bleeding on probing (black band entirely visible) Oral hygiene instructions
2 Pockets <3.5mm, supra or subgingival calculus/overhangs (black band entirely visible) As for code 1, plus removal of plaque-retentive factors, including all supra- and subgingival calculus
3 Probing depth 3.5-5.5mm (black band partially visible, indicating pocket of 4-5mm) As for code 2, and root surface debridement if required
4 Probing depth >5,5mm (black band disappears, indicating pocket of 6mm or more) Oral hygiene instructions, root surface debridement, assessment of need for more complex treatment
* Furcation involvement Treatment according to codes 0 to 4, assessment of need for more complex treatment

All new patients should have the basic periodontal examination recorded, however the basic periodontal examination should not be used around implants (4 or 6-point pocket charting is advised).

X-ray radiographs may be used to support a clinical diagnosis and to monitor bone loss.

If a periodontic and endodontic lesions coalesce, this is known as a periodontic-endodontic (perio-endo) lesion. In these cases, the acute infection must be managed through drainage (systemic antibacterial agents may be required) and following this, root canal treatment can be initiated.

Necrotising periodontal diseases are painful and destructive with ulcerated necrotic papillae (‘punched out appearance’). Aggressive periodontitis is rare, however it may be rapidly progressive with no obvious risk factors. It tends to occur in families and an early age of onset. The amount of plaque present is usually disproportionate to the severity of periodontal destruction. Aggressive periodontitis is often associated with the bacterial pathogens aggregatibacter actinomycetamcomitans and porphyromonas gingivalis. There are two main forms, generalised and localised aggressive periodontitis. Treatment is through sub- and supragingival plaque control and regular supportive care. In some cases, adjunctive systemic antibiotics and surgery is indicated.

If pus collects in the tissues adjacent to a periodontal pocket, this is known as a periodontal abscess. These commonly occur in furcations. As the tooth may be tender to percussion and painful, it is important not to misdiagnose this as periapical periodontitis. The tooth will usually be vital and mobile and lateral movements will elicit pain. Incision and drainage under local anaesthesia is recommended and a 5 day course of systemic antibiotics. After emergency management of the acute infection, mechanical débridement is necessary and conventional treatment of the existing periodontal pocket.

Further reading: Restorative dentistry