A dental crown is a custom-made, tooth-shaped cap used to restore a damaged or weakened tooth. Crowns protect the remaining natural tooth structure, restore function, and improve appearance. Although durable, the bond holding them in place can fail, causing the crown to become loose or fall off completely. Knowing what to look for and what steps to take can help preserve the tooth until you see a dentist.
Identifying the Fallen Dental Crown
A dislodged crown looks like a hollow replica of your tooth, typically crafted from porcelain, zirconia, or metal. The exterior is smooth and contoured, often colored to match your other teeth. Turning it over reveals the recessed, concave underside that was cemented onto the prepared tooth structure.
Inside this hollow space, you may see residue from the dental cement, which often appears chalky or as hardened, off-white glue. If the crown covered a tooth that had a root canal, you might also see a thin, rigid post structure adhered inside. The presence of this post suggests a failure of the underlying core buildup.
The exposed tooth (abutment or preparation) will feel much smaller than a typical tooth, as the dentist filed it down so the crown could fit. This prepared structure may look dark or discolored and will likely be sensitive to temperature or air because the protective enamel is gone.
Immediate Steps for Handling the Situation
The first step is to find the crown. Gently rinse it with warm water to clean off debris, but avoid scrubbing or using harsh soaps. An undamaged crown can often be reattached, so store it safely in a small, sealed container to bring to your appointment.
Immediately contact your dental office to schedule a repair appointment, as a lost crown is a high-priority issue. While waiting, care for the newly exposed, sensitive tooth. Avoid chewing or biting on that side of your mouth to protect the prepared tooth from fracturing. Rinsing your mouth with warm salt water can help keep the area clean and reduce irritation.
If the tooth is causing extreme sensitivity and you cannot see a dentist quickly, attempt a temporary fix using an over-the-counter dental cement kit. Dry the exposed tooth and the inside of the crown, apply cement, and gently fit it back onto the tooth. This is a short-term measure to reduce sensitivity, but professional re-cementation is still required.
Common Causes of Crown Dislodgement
The most frequent reason a crown falls out is the failure of the dental cement. The adhesive bond weakens over time due to wear, saliva, and the daily forces of chewing. As the cement deteriorates, the crown’s retention is compromised, causing it to become loose.
A second cause is new tooth decay beneath the crown’s margin. Bacteria can infiltrate this area, especially with an imperfect fit, leading to a cavity in the underlying structure. As decay erodes the prepared tooth, the base shrinks, causing the crown to lose its secure fit and fall off.
Physical factors like trauma or excessive force also play a role. Biting down on a hard object can break the cement bond. Additionally, habitual teeth grinding or clenching (bruxism) places constant pressure on the crown, accelerating wear and potentially fracturing the tooth or crown itself.
Professional Solutions for Reattaching or Replacing the Crown
When you visit the dentist, the initial step is a thorough examination of both the fallen crown and the exposed tooth. The dentist assesses the crown for damage and checks the prepared tooth for decay or fractures. If the crown is intact, the underlying tooth is healthy, and the fit is precise, the dentist cleans both surfaces to remove old cement.
The most straightforward resolution is re-cementation, using a strong, permanent adhesive to bond the original crown back onto the tooth. This process is quick and effective when failure was due solely to cement fatigue. The dentist isolates the tooth, applies new cement inside the crown, and presses it firmly back into place.
A replacement crown is necessary if the original crown is cracked, if significant new decay has formed, or if the tooth has fractured. If decay is found, the dentist removes the carious tissue, which alters the tooth’s shape. The dentist then prepares the tooth again, takes a new impression, and sends it to a lab for fabrication of a new crown.