A dental crown is a custom-made cap designed to cover a damaged or weakened tooth, restoring its shape, size, strength, and appearance. While crowns are meant to be long-lasting, permanent restorations, they can come off. Various factors can compromise the secure bond between the crown and the natural tooth structure underneath. Knowing what to do when this common dental event occurs protects the exposed tooth from further damage and sensitivity.
Why Dental Crowns Detach
The most frequent cause of crown detachment is the failure of the dental cement used to secure it to the underlying tooth preparation. Over time, the cement degrades due to constant exposure to saliva, temperature fluctuations, and the substantial forces of chewing. This degradation often weakens the seal gradually.
Tooth decay developing underneath the crown is another major contributor to loosening. If bacteria penetrate the margin where the crown meets the tooth, the resulting decay erodes the natural tooth structure. This loss of supporting material compromises the crown’s stability, causing it to lose its tight fit and eventually fall off.
Excessive force on the tooth can also dislodge the restoration. Habits like teeth grinding (bruxism) and clenching place immense pressure on the crown, weakening the bond over time. Biting down on hard items, such as ice or unpopped kernels, or pulling at the crown with sticky foods, can apply enough immediate force to break the seal.
Immediate Steps When a Crown Comes Off
The first step after a crown detaches is to retrieve it to prevent swallowing or inhaling it. Gently clean the crown with warm water to remove debris or old cement, avoiding harsh chemicals that could cause damage. Store the crown safely in a small, clean container for your dental appointment.
The exposed tooth is now vulnerable to sensitivity and potential damage. Gently clean the tooth surface using a soft toothbrush and mild toothpaste, and avoid chewing on that side of your mouth. If the exposed tooth feels sharp or rough, dental wax or sugar-free gum can be placed over the edges to protect your tongue and cheek.
If you cannot see a dentist immediately, temporarily re-securing the crown offers short-term protection. Over-the-counter temporary dental cement, available at most pharmacies, can be applied to the inside of the crown before seating it back onto the tooth. Petroleum jelly or toothpaste can also act as a temporary cushion to hold the crown in place until professional care is available. Contact your dental office as soon as possible to schedule a proper re-cementation.
Repairing or Replacing the Crown
The dentist begins by determining why the crown detached. They will examine the crown for damage and the underlying tooth structure, often using an X-ray to check for recurrent decay or fractures beneath the surface. This evaluation ensures the tooth is restorable and has sufficient structure remaining to support the restoration.
If the crown is intact and the underlying tooth is healthy, the dentist cleans both the tooth and the inside of the crown to remove old cement and debris. A specialized, permanent dental cement is then applied to re-bond the crown securely. This re-cementation process is quick, preserves the original restoration, and is typically the most cost-effective solution.
If the crown is fractured, damaged beyond repair, or if significant decay is found underneath, a replacement crown is necessary. The dentist will remove decay, potentially reshape the tooth, and take new impressions to create a custom-fitted crown in a dental laboratory. A temporary crown is placed until the new restoration is ready to be bonded into place.
Maintaining Dental Crowns
Protecting the crown’s margins and underlying tooth from decay and mechanical stress requires diligent oral hygiene. This includes brushing twice daily with a soft-bristled toothbrush, paying close attention to the gumline where the crown meets the tooth. Flossing carefully around the crowned tooth removes plaque and food particles that accumulate at the crown’s edge.
Dietary modifications reduce the risk of dislodgement. Avoid excessively sticky foods, such as caramels or chewing gum, which exert a pulling force on the crown. Hard foods like nuts, hard candies, or ice should be avoided to prevent chipping the crown or fracturing the underlying tooth structure.
If you habitually grind or clench your teeth, discuss a custom-fitted nightguard with your dentist to mitigate the forces of bruxism. Regular dental check-ups, typically twice a year, allow the dentist to monitor the integrity of the crown’s seal. This helps detect early signs of decay or a poor fit before the crown completely detaches.