Pulpitis is inflammation of the dental pulp, the soft connective tissue containing nerves, blood vessels, and lymphatics housed within the pulp chamber and root canals of a tooth. It ranks among the most common causes of acute dental pain and typically develops from untreated dental caries, traumatic injury, or repeated operative procedures that erode the protective layers of enamel and dentin.

Reversible vs. Irreversible Pulpitis

Clinicians classify pulpitis into two primary forms based on the pulp’s capacity to recover:

Reversible pulpitis occurs when the pulp remains vital and capable of healing once the source of irritation is removed — such as a shallow carious lesion or a recently placed restoration. Pain is typically sharp, brief, and triggered by thermal stimuli, subsiding quickly once the stimulus is gone.

Irreversible pulpitis indicates that the pulp has sustained damage beyond its ability to recover. Pain is often spontaneous, lingering, and severe. Without intervention, the condition progresses to pulp necrosis and periapical pathology that threatens surrounding structures.

Common Symptoms

• Sharp, transient pain in response to hot or cold stimuli (characteristic of the reversible form)
• Spontaneous, throbbing, or prolonged pain that lingers after the stimulus is removed (characteristic of the irreversible form)
• Heightened sensitivity to sweet or acidic foods
• Pain that worsens when lying down or with postural changes
• Referred pain to adjacent teeth or the jaw

Diagnosis and Treatment

Accurate diagnosis relies on thermal pulp testing, electric pulp testing, and periapical radiographs, which help assess the pulp’s vitality and the status of the surrounding periodontal ligament. A detailed pain history — including the duration, character, and provoking factors — is essential for distinguishing reversible from irreversible disease.

Treatment follows the clinical classification: reversible pulpitis is managed by removing the offending stimulus and placing an appropriate restoration, allowing the pulp to recover; irreversible pulpitis requires root canal therapy or extraction to eliminate inflamed or necrotic tissue and prevent the spread of infection to periapical structures.

Pulpitis rarely resolves on its own — prompt dental evaluation at the first sign of persistent or spontaneous tooth pain is the most reliable way to preserve the tooth and avoid more extensive treatment.