A temporary crown is a protective covering placed over a tooth prepared for a permanent crown. This provisional restoration shields the newly shaped, often sensitive tooth structure while the final crown is fabricated in a dental laboratory. The temporary cap also maintains necessary space and alignment with adjacent teeth, preventing shifting that could compromise the fit of the permanent crown. Typically made of acrylic or composite resin, the temporary crown is designed for a limited lifespan, usually two to three weeks. It is secured with a temporary dental cement that is intentionally less adhesive than the final bonding material.
Common Reasons for Temporary Crown Failure
The primary factor contributing to dislodgement is the deliberate weakness of the temporary cement, which is formulated for easy removal by the dentist during the final appointment. This low bond strength means the crown is only held in place by minimal adhesion and the mechanical grip of the tooth’s preparation shape. Chewing forces represent the most common mechanical challenge to this delicate bond, especially if the temporary crown receives excessive pressure or has a slight “high spot” in the bite.
Occlusal interference, or uneven contact during biting and chewing, can create lever-like forces that gradually break the temporary cement seal. Habits like teeth grinding or clenching also exert sustained, intense pressure that stresses the provisional restoration’s retention. Furthermore, certain foods, particularly those that are sticky, hard, or chewy, can physically pull the crown away from the prepared tooth surface.
The underlying preparation shape of the natural tooth also affects retention; if the prepared tooth is overly smooth or lacks sufficient height, the temporary crown has less surface area to grip. Material degradation or fracture of the acrylic temporary can occur if subjected to repeated, heavy impact. Repeated dislodgement may also indicate a potential issue with the underlying tooth, such as recurrent decay or a marginal fracture.
What to Do Immediately When a Crown Falls Off
If your temporary crown becomes dislodged, retrieve it carefully and rinse it gently with warm water to remove any debris. Inspect both the crown for any cracks and the underlying prepared tooth structure for any sharp edges or remaining cement. Contact your dental office immediately to schedule an urgent re-cementation appointment, as leaving the prepared tooth exposed can lead to complications.
The exposed tooth is vulnerable to sensitivity, particularly to temperature changes, and is at risk of bacterial contamination. Over-the-counter pain relievers, such as ibuprofen, can help manage any immediate discomfort or tenderness. You can also use temporary dental wax or sugar-free gum to place over the sharp edges of the exposed tooth structure to protect your tongue and cheek until you can reach the dentist.
If you are unable to see the dentist right away, you can attempt a short-term re-cementation using an over-the-counter temporary dental cement kit or denture adhesive. Clean the inside of the crown and the tooth surface, dry both thoroughly, apply a minimal amount of adhesive to the inside of the crown, and seat it firmly in place. Ensure the crown is properly aligned and not too high when biting down. This home fix is not a substitute for professional care and should only be used as a stopgap measure.
Professional Repair and Assessment
The professional repair process begins with a thorough assessment of both the exposed tooth and the dislodged crown. The dentist inspects the prepared tooth structure for any new damage, fractures, or signs of decay that may have caused the initial failure. They will also check the temporary crown itself for structural damage that would necessitate fabricating a new provisional restoration.
Next, the old, failed temporary cement must be meticulously cleaned from both the inside of the crown and the surface of the prepared tooth. The tooth surface is then isolated and dried to create the best possible conditions for the new adhesive bond. A fresh batch of temporary cement, often a zinc oxide-based material, is mixed and applied to the crown, which is then firmly seated onto the prepared tooth.
After the temporary crown is seated, the dentist checks the patient’s bite, or occlusion, to ensure there are no premature or heavy contacts that could cause the crown to dislodge again. Any excess cement is removed from the margins, and the bite is adjusted using specialized instruments to reduce the stress on the temporary restoration before the final crown is ready.
Preventing Future Dislodgement
Maintaining a temporary crown requires intentional modifications to your daily habits to prevent mechanical dislodging forces. The most important change involves dietary choices, specifically avoiding foods that are hard, sticky, or exceedingly chewy. These types of foods can grab the restoration and pull it straight off the tooth.
Foods to avoid include:
- Tough meats
- Caramel
- Chewing gum
- Sticky candies
When eating, it is strongly recommended to chew primarily on the side of the mouth opposite the temporary crown to minimize direct impact forces. Even if you are eating softer foods, direct pressure can still compromise the temporary cement bond over time.
Oral Hygiene Care
For oral hygiene, continue to brush the area gently, but exercise specific care when flossing. Instead of pulling the floss up and out between the teeth, which can catch the crown’s edge and lift it off, slide the floss out horizontally from the side. If you are known to grind your teeth, discussing a protective nightguard with your dentist is beneficial, as the constant nocturnal pressure can significantly loosen the provisional restoration. These careful habits ensure the temporary crown remains a stable placeholder until the permanent restoration is cemented.