▪ What specific questions would you ask with regard to the history of pain?

Relevant questions are shown below, together with the patient’s answers.

▪ On the basis of what you know already, what is the likely diagnosis?

The pain is almost certainly pulpitis. It is brought on by hot and cold and is poorly localized. It has progressed from intermittent pain, suggesting reversible pulpitis, to a severe pain that lasts hours. The severity and duration now suggest that pulpitis might be irreversible.

▪ What is irreversible pulpitis?

Irreversible pulpitis is a concept rather than a well-defined clinical condition. Pulpitis is usually chronic and progresses intermittently and unpredictably with or without acute phases. At some stage the pulp must be irretrievably damaged, probably because pressure from inflammation compresses the pulpal veins and arteries. This causes loss of vitality. The ability to predict that a pulp will die would be useful when deciding possible treatments. Unfortunately, the clinical symptoms that accompany pulpitis are very variable, especially in multirooted teeth, and pain is a subjective sensation. Severe pain of long duration, spontaneous pain and waking at night are usually taken to indicate the irreversible stage of pulpitis but predicting the future is never reliable and making this diagnosis involves an element of uncertainty.

▪ What parts of the examination would be most useful? Why?

Teeth should be percussed to establish whether any are tender. Adjacent, apparently healthy control teeth should be percussed first for comparison. Tenderness indicates inflammation in the periodontal ligament and causes would include very late stage irreversible pulpitis or a necrotic pulp.

Palpation of the mucosa overlying the tooth apices with a fingertip. Tenderness indicates extension of inflammation from the periodontal ligament to the surrounding bone and the activity of any inflammation present. Compare with apparently normal teeth. Lower molar apices are close to the lingual mandibular cortex and must be palpated lingually as well as buccally.

Periodontal probing to detect loss of attachment or exposed dentine. Dentine hypersensitivity would not cause such severe, long-lasting pain. However, pocketing or previous periodontal treatment could have exposed a lateral canal or canal in the furcation, allowing bacteria access to the pulp.

Search for a sinus. This would indicate periradicular infection. Sinuses may heal and present as a small fibrous nodule indicating past or intermittent infection. The search must include lingual alveolar mucosa because the apices of lower molars lie closer to the lingual than buccal cortex.