A dental crown is a custom-made cap placed over a damaged tooth to restore its shape, size, strength, and appearance. These restorations are bonded permanently to the prepared tooth structure using a specialized dental cement. While crowns are intended to last many years, the adhesive bond is not indestructible, and the crown may occasionally come loose or fall off completely. This failure often results from the gradual degradation of the dental cement over time, or from decay forming underneath the crown at the margin. This decay compromises the supporting tooth structure and weakens the seal, but in many cases, the original crown can be successfully reattached.
Immediate Steps After a Crown Falls Off
If a crown detaches, carefully retrieve it to prevent swallowing or accidental damage. Rinse the crown gently with water and store it safely, such as in a small, clean container or plastic bag, before contacting the dental office immediately. The exposed tooth underneath may feel sensitive to temperature or pressure, and it is important to avoid chewing on that side of the mouth. The underlying tooth may also have sharp edges, which can be temporarily covered with a small piece of dental wax or sugar-free gum to protect the cheek and tongue. Over-the-counter temporary dental cement can be used as a short-term measure to seat the crown back onto the tooth, but this should only be done if the crown is intact and seats easily without force; household adhesives should never be used.
Factors Determining Reattachment Success
The possibility of reattaching the existing crown depends entirely on a clinical assessment by the dentist, focusing on the condition of both the crown and the underlying tooth. The crown itself must be intact and undamaged, meaning it should not be fractured, cracked, or chipped, as a compromised crown cannot provide adequate long-term protection. The underlying tooth structure is the most critical factor for successful reattachment. If significant new decay (caries) has developed beneath the crown, or if the remaining tooth has fractured, simple re-cementing will not suffice, and the decay or fracture must first be treated. If the supporting tooth is healthy and the crown is undamaged, the fit is assessed; if the crown no longer fits precisely due to changes in the tooth or if the remaining tooth is too short to provide retention, a new crown must be fabricated to ensure a proper seal.
The Professional Recementing Procedure
When the dentist determines the crown can be reused, the procedure begins by thoroughly cleaning the inside surface of the crown and the prepared tooth structure to remove old cement, debris, and bacteria. The tooth surface is then isolated, typically using cotton rolls or a rubber dam, to ensure the area remains completely dry during the bonding process, which is essential for the cement to achieve maximum strength. The dentist tries the crown back onto the tooth to confirm the fit and check the bite alignment before proceeding. A fresh batch of specialized dental cement (which may be resin-based or glass ionomer) is mixed and applied to the inner surface of the crown, which is then firmly seated onto the tooth. After the cement is fully set, any excess material around the crown margins is meticulously removed, and the bite is checked once more to ensure the restoration does not interfere with the patient’s occlusion. This professional process restores the seal, protects the underlying tooth from further damage, and is generally a quick appointment.