A dental crown is a custom-made cap placed over a damaged or weakened tooth, designed to restore its natural shape, strength, and appearance. They are bonded to the prepared tooth structure using a specialized dental cement. While crowns are constructed from durable materials like porcelain or metal, they can occasionally come loose or fall off completely. This event, though unsettling, is a relatively common occurrence that necessitates prompt attention from a dental professional.
Reasons Why Crowns Loosen
The most frequent cause for a crown becoming dislodged is the gradual failure of the dental cement that holds it securely to the tooth. This adhesive bond is constantly exposed to the oral environment, and over time, it may degrade or wash out due to the consistent presence of saliva and chewing forces. The breakdown of this cement weakens the connection between the crown and the underlying tooth structure, allowing the restoration to loosen over time.
A significant factor is the development of tooth decay at the crown’s margin, where the edge of the cap meets the gumline. Even with a crown in place, the natural tooth underneath remains susceptible to bacterial plaque accumulation and subsequent decay. As the decay progresses, it erodes the underlying tooth structure that supports the crown, causing the prepared tooth to shrink or collapse. This loss of foundational material means the crown no longer fits tightly, allowing it to move and eventually separate from the tooth.
Physical stress also contributes heavily to crown failure, especially in individuals who grind or clench their teeth, a condition known as bruxism. The immense, repetitive forces generated by bruxism place undue pressure on the crown and its cement bond, accelerating wear and tear. Additionally, chewing on extremely hard foods, like ice or nuts, or sticky foods, such as caramel, can generate enough force to physically break the bond or pull the crown away from the tooth.
Immediate Steps When a Crown Comes Off
If your crown comes loose or falls out, the first immediate action is to retrieve the crown to prevent swallowing it and to store it safely in a small container. Gently rinse both the crown and your mouth with warm water to clean any debris from the exposed tooth. The natural tooth underneath is now vulnerable, often appearing small and sensitive to temperature changes or air flow.
Contact your dental office immediately to schedule an appointment, informing them that your crown has become dislodged. While waiting for your appointment, you can attempt a temporary measure to protect the exposed tooth and relieve sensitivity. If the crown is intact and undamaged, you may use over-the-counter temporary dental cement, available at most pharmacies, to temporarily re-secure it.
Clean the inside of the crown and the tooth surface thoroughly, dry both areas with gauze, and apply a small amount of the temporary cement inside the crown before gently seating it back onto the tooth. This is a short-term fix intended only to protect the tooth and should not be considered a permanent solution. Avoid chewing on the side of the mouth with the loose crown, regardless of whether you have temporarily reattached it. Take over-the-counter pain relievers if the exposed tooth is sensitive.
Professional Treatment Options
Once you arrive at the dental office, the dentist will conduct a thorough assessment, beginning with a visual examination of the crown and the remaining tooth structure. An X-ray is typically taken to check for underlying issues, such as tooth decay or a fracture in the root. The condition of the tooth beneath the crown determines the subsequent course of professional treatment.
If the crown is in good condition and the tooth structure is relatively sound, the dentist will clean both surfaces meticulously and re-cement the existing crown using a permanent dental cement. This is the simplest resolution. However, if the underlying cause was significant decay, the decayed material must be removed and the remaining tooth restored with a filling or a core build-up before the crown can be re-bonded.
If the crown itself is fractured, chipped extensively, or if the underlying tooth structure is too compromised, a replacement will be necessary. The dentist will take new impressions or scans to fabricate a custom-made crown, and a temporary crown will be placed to protect the tooth in the interim. In cases where the decay is very deep and has reached the inner pulp of the tooth, a root canal procedure may be required to eliminate the infection before any new restoration can be placed.
Keeping Your Crown Secure
Long-term security of a dental crown relies heavily on consistent, meticulous oral hygiene, especially around the crown’s margin. Brushing twice daily with a fluoride toothpaste and flossing once a day helps prevent the accumulation of plaque and bacteria at the gumline. When flossing, it is helpful to gently slide the floss out sideways rather than snapping it upward to avoid inadvertently dislodging the crown.
Patients should avoid biting directly into hard items such as ice, hard candies, or non-food objects like pens, as this can fracture the crown material. It is also advisable to limit consumption of sticky or chewy items that can potentially grab onto the crown and weaken the cement bond. For individuals who exhibit nighttime teeth grinding, a custom-fitted night guard can effectively manage the excessive occlusal forces, protecting the crown and the surrounding teeth from undue stress. Regular dental checkups allow the dentist to professionally monitor the crown’s fit and the health of the underlying tooth.