When we think of teeth, we imagine them to be solid with no soft parts to them. In truth, while the outside of our teeth are strong, the inside is made up of blood vessels, cells, and tissues called dental pulp. For a variety of reasons, this pulp can become infected and quickly die, resulting in a necrotic tooth. When there is no living tissue left in a tooth, the inside becomes an easy host for bacteria. These can move to other teeth or cause other issues in the body.

What are the causes of pulp necrosis?

Some form of periapical periodontitis is more common than you might think in people of all ages. Incidence of infection in and around the tooth root increases with age. It’s higher than you might think, occurring in:

  • 33% of people aged 20 to 30
  • A high rate of 62% of people over the age of 60

As people age, their ability to fight infection (and the presence of other complicating factors, like diabetes or immune system disorders) makes necrotic teeth more common. What are some of the other causes?


Traumatic injury such as a blow to the jaw or specific teeth may cause openings in the teeth for bacteria to enter.

Chronic cavity

Cavity can lead to a whole host of issues.

When teeth are subjected to repeated dental work, including drilling and filling cavities, the hard parts of the teeth are compromised and become perfect entry points for bacteria. Infections, left undetected or untreated, can lead to pulp necrosis. Always working with a highly-qualified dentist can help reduce this risk.

Rapid orthodontic treatment

While orthodontics are necessary to correct misalignment in the jaw and with the bite, correction that occurs too rapidly can injure the roots of the teeth.

Periodontal disease

Periodontal disease is a blanket term for a number of different dental diseases including gingivitis and periodontitis.

These are very treatable but can have serious complications if left untreated, including dental abscess and even, in rare cases, death.

Calcific metamorphosis

This condition is more rare but does occasionally result in necrotic teeth. The cells that form the hard dentin layer of the teeth begin to produce excess calcium deposits inside the tooth. This shrinks (or completely eliminates) the root canal so that the tooth reads as necrotic. While there may still be life in the tooth, your dentist may not be able to save it.

A necrotic tooth is sometimes referred to as a non-vital tooth. This doesn’t mean that the tooth doesn’t matter; rather, the tooth is no longer living and is not vital (as in vital, or living, organs).

What’s used to diagnose a necrotic tooth?

If it’s true that the squeaky wheel gets the grease, the necrotic tooth may go unnoticed for a long period of time. Necrotic teeth eventually lose all sensation, including pain, regardless of the stimulus (i.e., hot, cold, or pressure). A tooth that has been aching may suddenly not hurt anymore, leading the patient to believe that perhaps the problem has resolved itself.

One of the prime symptoms of necrotic teeth is a slight darkening of the tooth as the dentin inside the tooth becomes discolored. Once pain disappears and the tooth begins to discolor, the tooth may be necrotic.

Before the pain disappears, though, there are a number of ways to diagnose a necrotic tooth.

Patient history

A thorough patient history may help diagnose a (potentially) necrotic tooth. This might reveal injury or trauma that can lead to necrosis.

Pulp testing with different stimuli

Your dentist will measure nerve and sensory response to a variety of stimuli, including low-level electric current, pressure, heat, and cold. A dentist will apply any or all of these to multiple teeth in the area of pain to determine the exact, affected tooth.


Because swelling and pain can be present in a variety of dental conditions, your dentist may use a d