A dental crown is a custom-made, tooth-shaped cap placed over a damaged or weakened tooth to restore its form, size, and strength. While this restorative treatment is designed for durability, crowns are not meant to last indefinitely, typically functioning effectively for 5 to 15 years before they need attention. Factors like material wear, changes to the underlying tooth, or shifting gum lines necessitate the process of replacement. Replacing a crown is a common procedure that dentists perform to ensure the ongoing health and function of the underlying tooth structure.
Signs That a Crown Needs Replacing
Persistent pain or heightened sensitivity to temperature or pressure when biting often indicates an issue, such as decay forming beneath the crown or a fracture in the restoration itself. The presence of visible damage, like a chip in the porcelain or a crack spanning the surface, compromises the protective seal and structural integrity of the crown.
Gum recession around the crowned tooth can expose the edge of the restoration, sometimes revealing a dark line, particularly with porcelain-fused-to-metal crowns, which is an aesthetic concern. A crown that feels loose or exhibits movement when chewing suggests that the bonding cement has weakened, allowing bacteria to infiltrate and potentially cause infection or decay. Furthermore, a routine dental X-ray may reveal recurrent decay or a compromised fit at the crown’s margin, even before a patient experiences noticeable symptoms.
The Clinical Procedure for Crown Removal and Preparation
The crown replacement process typically requires two appointments, beginning with a thorough assessment and the administration of local anesthesia. During the first visit, the dentist removes the existing crown, often by sectioning it with a high-speed dental bur, which breaks the cement seal without harming the underlying tooth structure. Once the old crown is lifted away, the dentist cleans the remaining tooth material and assesses it for any signs of decay or structural damage.
Any decay is removed, and the remaining tooth is treated to establish a clean, healthy foundation for the new restoration. The tooth is then re-contoured and reshaped, ensuring proper dimensions so the new crown will fit securely and align correctly with the patient’s bite. An accurate impression of the prepared tooth is then recorded, either using a putty-like material or a modern digital scanner, which is sent to a dental laboratory for the custom fabrication of the permanent crown.
Before the patient leaves, a temporary crown is bonded onto the prepared tooth using a weaker, provisional cement to protect the exposed dental tissue and maintain the space while the permanent crown is being made. The second appointment, usually scheduled two to three weeks later, involves removing the temporary crown and trying in the new, permanent restoration. The dentist confirms the crown’s fit, color match, and bite alignment before securely bonding it to the tooth with durable dental cement.
Material Options and Selection Considerations
The choice of material for the new crown depends on the tooth’s location, functional demands, and aesthetic desires.
- All-Porcelain or All-Ceramic crowns offer the most natural appearance due to their light-reflecting properties, making them preferred for highly visible front teeth. Traditional ceramics may be less resistant to fracture under heavy biting forces.
- Zirconia is a highly durable ceramic material that provides exceptional strength, rivaling metal while maintaining a tooth-colored appearance suitable for both front and back teeth.
- Porcelain-Fused-to-Metal (PFM) crowns balance strength and aesthetics, using a metal substructure for resilience and a porcelain layer for a natural look. The metal margin may eventually become visible near the gum line.
- Gold alloy crowns are recognized for their superior longevity and biocompatibility, often chosen for back molars where strength and resistance to wear are prioritized.
Managing Recovery and Long-Term Maintenance
Following the placement of a new crown, some mild sensitivity to hot and cold temperatures is normal and should lessen over a few days. Any discomfort can typically be managed with over-the-counter pain relievers and rinsing the mouth with warm salt water to soothe the gums. It is advisable to avoid chewing hard or sticky foods for the first 24 to 48 hours after the permanent crown is cemented to allow the bonding agent to fully cure.
For the temporary crown period, patients should chew on the opposite side of the mouth and avoid sticky items like gum or caramels that could dislodge the temporary restoration. Long-term maintenance requires diligent oral hygiene, including brushing twice a day with a soft-bristled brush and flossing carefully around the crown to prevent plaque buildup at the margin. Regular dental check-ups are also important so the dentist can monitor the crown’s integrity and the health of the surrounding gum tissue.