The pulp and the periodontal ligament are closely connected via:
• The apex or apices
• Other vascular channels (e.g. lateral and furcation canals)
• Dentinal tubules
Therefore, it is not surprising that there should be a relationship between diseases of the pulp and the periodontium. In determining the treatment for a particular tooth it is essential to know whether the initial lesion is of periodontal or endodontic origin.
The following classiﬁcations of endodontic and periodontal lesions have been proposed:
• Lesions of endodontic origin
• Periodontal lesions
• Primary endodontic/secondary periodontal
• Primary periodontal/secondary endodontic
• Combined endodontic/periodontal lesions
Lesions of endodontic origin
Lesions of endodontic origin are simple periapical or lateral periodontal granulomas (chronic apical/lateral periodontitis characterised by aggregations of macrophages, lymphocytes and plasma cells) and abscesses (acute apical/lateral periodontitis) recognised by the usual clinical and radiographic features.
Periodontal lesions are diagnosed on the basis of generally accepted criteria including derangement of gingival architecture and loss of ging-ival attachment as demonstrated by pocket probing and radiographs.
Primary endodontic/secondary periodontal
Endodontic disease may masquerade as periodontal disease in several ways:
• Drainage of a periapical lesion via the periodontal ligament, perhaps perforating the gingivae at, or near to, the mucogingival junction, or exiting via the gingival crevice.
• Endodontic lesions formed via lateral canals at places on the root surface other than at the apex.
• Lateral perforation of the root during root canal or post preparation leading to a lateral periodontal abscess which may drain via the gingival crevice.
• Endodontic lesions in furcation areas formed via ‘lateral’ canals leading to abscesses, sinuses and radiographic bone loss, which may look like periodontal disease.
Primary periodontal/secondary endodontic
Chronic periodontitis may lead to pulpal disease by means of direct bacterial invasion, or trauma during root surface instrumentation as part of treatment. Chemicals and obtundents used to relieve dentine sensitivity may irritate the pulp, as may the exposure of root surfaces by gingival recession. There is some disagreement in the literature about whether this really happens, mainly because many teeth with signiﬁcant periodontal disease also have large restorations, so it is impossible to know whether the pulpal lesion was caused by caries, restoration or periodontitis.
Combined endodontic/periodontal lesions
Combined endodontic/periodontal lesions may be:
• Independent of one another
Differential diagnosis is based upon interpretation of information gained from the following:
pain (duration and character)
• Clinical examination:
swelling (site, type and character)
discharge (type of ﬂuid, blood, pus etc.)
percussion (gentle percussion in several directions)
• Special tests:
vitality/sensibility testing (electrical and/or thermal, mechanical)
radiographs (parallax views if necessary)
In determining the treatment to be provided, an assessment of the vitality of the tooth in question is required. In some instances, it may not be clear whether the pulp is vital or not. In these cases a judgement must be made based on the available evidence from the history and clinical appearance (including special investigations) and treatment instigated. The options for treatment are summarised below:
• Pulp judged to be healthy:
reassessment: if unsuccessful commence endodontic therapy. If successful no further treatment.
• Pulp judged to be unhealthy:
reassessment: if unsuccessful commence periodontal therapy. If successful no further treatment.
A Case of Perio- Endo Lesion.....