Reversible Pulpitis

Reversible pulpitis is mild inflammation of the dental pulp that resolves when the cause is removed. Pain is short, sharp and provoked, and stops within seconds after the stimulus is gone.

It is the first stage of pulp response to caries, a leaking restoration, recent dental work, cracks, exposed dentine or heavy occlusal contact.

Pathophysiology. Bacterial products or thermal and chemical irritation cross open dentinal tubules and cause a local inflammatory response in the pulp, with low grade vasodilatation and fluid movement across the tubules that stimulates A-delta fibres.

The pulp is still vital and capable of healing, with deposition of tertiary dentine, if the stimulus is removed early.

Brief, sharp pain on cold, sweet or sometimes hot stimuli that resolves within seconds (usually under 10 to 15 seconds) after removing the stimulus. There is no spontaneous pain and no pain on lying down. Patients can point to the tooth.

There is no tenderness on percussion or palpation, and the tooth is not mobile. Look for caries, a defective restoration, a crack, recession or a recently placed deep filling.

Pain that lingers, wakes the patient at night or starts spontaneously suggests irreversible pulpitis, and facial swelling or fever suggests spreading infection.

• History of provoked, short pain, with the tooth identified by testing.
• Cold test (refrigerant spray or ice stick) and electric pulp test: a response that is brief and returns to baseline in under 10 to 15 seconds. Compare with the adjacent and opposing teeth.
• Percussion and palpation are normal, and periodontal probing is normal.
• Bitewing and periapical radiographs: caries depth, proximity to the pulp, a normal periapical area and normal periodontal ligament space.
• Transillumination and bite test to look for a crack.

Differential diagnosis.

• Dentine hypersensitivity
• Irreversible pulpitis
• Cracked tooth syndrome
• Food impaction or an open contact
• Post-restoration sensitivity or pulp irritation by materials
• Interproximal caries under a restoration
• Barodontalgia, sinusitis or referred pain

• Remove the stimulus: excavate caries and restore. In deep caries, use selective removal to soft dentine and a seal, or stepwise excavation, in preference to complete removal, to avoid exposing the pulp.
• Indirect pulp capping with a calcium silicate cement or calcium hydroxide liner over the deepest dentine, and a glass ionomer or resin modified base before the final restoration, which has a success rate of about 85 to 95%.
• Replace a leaking restoration, adjust high occlusal contacts, and protect a cracked cusp with a cuspal coverage restoration.
• Dentine hypersensitivity: desensitising toothpaste (potassium nitrate or stannous fluoride), fluoride varnish 22 600 ppm, and a dentine sealant.
• Analgesia is seldom needed: ibuprofen 400 mg orally every 8 hours with food for 1 to 3 days if required, avoided in renal impairment, active peptic ulcer and in late pregnancy, or paracetamol 1 g every 6 hours (maximum 4 g daily).
• Antibiotics have no role.

Monitoring. Review at 4 to 6 weeks with cold and electric pulp tests and percussion, and radiographs at 6 and 12 months after deep restoration. Persistent pain, lingering sensitivity, a draining sinus or a periapical radiolucency indicate progression to irreversible pulpitis or necrosis.

Referral and escalation. Refer to an endodontist for a cracked tooth, repeated failure of pulp capping, or diagnostic doubt. Routine dental follow up is otherwise enough.