Pain from dental crown

Dental crowns (caps) are used to restore and protect the tooth structure from further damage due to decay, fracturing or cracking.  In some patients, the crown itself creates a new problem: pain and sensitivity.


The tooth crown (clinical crown) and dental crown are different:

Tooth crown is part of the tooth that is visible beyond the gums, the part that used to chew foods.

Dental crown (commonly known as cap or crown) is a type of dental restoration that fits over tooth crown.  Dental crown made of porcelain, gold or resin.


Why do some patients experience pain after crown cementation?

If the patient experiences sensitivity or pain immediately after crown cementation and before using the crown, the likely causes are:

1. Cement used; some types of cement may irritate and cause inflammation to the pulp tissue.


2. Rapid tooth reduction without adequate cooling water spray to overcome the heat generated during the crown preparation may irritate the pulp tissue.


3. Improper placing a crown.


4. Margin of the crown is too long, results in gum inflammation.


5. Dentin exposed to the oral environment due to shy margin (margin of the crown is too short).


6. Crown does not fit properly, may have open margin.


7. Large pulp chamber:
   When the dentist prepares the tooth for a crown, if the pulp chamber is large, grinding the tooth too close to the pulp chamber can irritate the pulp tissue and create pain.
   
   Pulp chamber is a housing for nerve and arteries supply to the tooth.  At a young age, pulp chamber is large due to the need for nutrition to the tooth, and it becomes smaller in old age.


8. Over-reduction of tooth structure (enamel and dentin) causing penetration to the pulp chamber.


9. Patients already had hypersensitive tooth before having the crown.
   
   

If the pain or sensitivity occurs after few days to weeks, the most likely causes are:

1. New crown has a high spot that is not in harmony with the rest of the teeth.  While chewing, a great deal of stress is applied to that place, results in sensitivity or pain.


2. The crown is not fitted correctly on the tooth.


3. The margin of the crown does not fit snugly into the tooth structure, creates a gap between the crown and the tooth. The space allows foods and drinks to penetrate inside the crown.


4. The margin is too long inside the gums, causing irritation and inflammation to the gums.


5. Loose contact between the crown and adjacent tooth, allowing food to trap in between, causing irritation and inflammation to the gums.


6. Improper maintenance - despite a good contact, if the patient does not floss, food can trap in between the crown and adjacent tooth, causing irritation and inflammation to the gums.


7. Cracked undetectable roots.  When the dentist places the dental crown on the tooth that has undetectable cracked root, creating more stress added to the root, results in a deeper crack that irritates the pulp tissue.

If the pain or sensitivity occurs after six months to present, the likely causes are:

1. Infection originates inside the tooth due to open margin, improper cleaning at the margin; leading to a dental cavity.
   
   
2. Infection caused by exposure to the pulp chamber during crown preparation.


3. Loose crown due to inadequate cement material.
    
4.  Patient unconsciously applies too much stress on the crown, e.g., clenching and grinding.


5. Food impaction between the crown and the adjacent tooth caused by open contacts or improper/inadequate cleaning at the contact area. Prolong food impaction may cause inflammation at the gums, a predisposed to the periodontal disease.


6. Fractured (cracked) roots can be an old undetectable or recent crack. When the crack reaches a pulp chamber, the patient often experiences pain or sensitivity.


7. Bite change due to periodontal disease or chipped tooth; the crown is no longer in harmony with the rest of the teeth.


8.  The shy margin or open margin results in decay underneath the crown.  Eventually, the decay reaches the nerve and patient experiences pain/sensitivity.

Assessment of tooth pain after having crown cemented requires a visual exam and x-rays by a dentist.