When tooth damage occurs, patients often face a choice between a filling and a crown. Restorative dentistry repairs the function and appearance of a tooth compromised by decay, fracture, or wear. The decision between a smaller repair (filling) and a full coverage restoration (crown) is specific to the individual tooth’s condition. Selecting the correct restoration is important for ensuring the long-term health and stability of the tooth.
When a Simple Filling is Sufficient
A dental filling is a suitable solution for minor damage. This procedure addresses small to moderate areas of decay, commonly known as cavities. The dentist removes the decayed portion, cleans the area, and fills the space to restore the tooth’s original contour and function.
The success of a filling depends on the remaining healthy tooth structure providing adequate support for the restorative material. Fillings are considered a conservative treatment because they preserve the largest amount of natural tooth material. Common materials include composite resin, which can be color-matched, and amalgam, a durable silver mixture. Composite resin fillings typically last 5 to 10 years, while amalgam can last 10 to 15 years, depending on care and location.
When Structural Support Requires a Crown
A dental crown, often called a cap, is necessary when the tooth has suffered extensive damage undermining its structural integrity. Unlike a filling, a crown is a custom-made covering that encases the entire visible portion of the tooth above the gum line. This comprehensive coverage restores the tooth’s full shape, size, and strength.
Crowns are indicated for teeth with very large failed fillings, severe fractures, or excessive wear. They are also routinely recommended after root canal therapy, as the procedure can make the tooth brittle and prone to fracture. The crown acts like a helmet, holding the weakened structure together and protecting it from the high forces of chewing. Crowns can be made from porcelain, metal alloys, or a combination of both, offering varying levels of strength and aesthetic appeal.
The Decisive Factors in Treatment Selection
The dentist’s recommendation is based on analyzing the extent of the damage and the biomechanical needs of the tooth. A primary factor is the size of the cavity or fracture relative to the tooth structure. If the damage affects more than 50% of the tooth width, a crown is required to prevent fracture.
The location of the tooth within the mouth also heavily influences the choice of restoration. Molars and premolars endure the heaviest chewing forces, making them more susceptible to fracturing if a large filling is placed. A crown provides the necessary full-coverage reinforcement to withstand these pressures.
A tooth that has had multiple previous fillings or one that has been endodontically treated (root canal) is significantly weakened and requires a crown for long-term survival. The remaining wall thickness of the tooth is a direct measure of its integrity.
If the natural tooth material remaining after decay removal is too thin, a filling will not be able to support the tooth against biting forces, leading to a high risk of cusp fracture. The full-coverage support of a crown is necessary to distribute the load across the entire tooth surface. Deep decay compromising the nerve may also require root canal therapy, which then necessitates a crown for protection.
Practical Considerations: Time, Durability, and Expense
The time commitment for each procedure presents a noticeable difference. A dental filling is straightforward and completed in a single appointment, often taking less than an hour. A crown procedure usually requires two appointments: one for preparation and impression-taking, and a second to cement the crown.
Crowns generally offer superior durability and longevity compared to fillings. Crowns can last 10 to 15 years, and sometimes 20 years or more with excellent care, due to their full-coverage design and stronger materials. Fillings typically have a shorter lifespan, often lasting between 5 and 10 years before requiring replacement or repair.
The cost difference between the two treatments is significant. Fillings are considerably less expensive upfront, often costing hundreds of dollars less than a crown. The higher expense of a crown is due to the complexity of the procedure, the cost of materials, and the involvement of a specialized dental laboratory. However, the greater longevity of a crown for severely compromised teeth can make it the more cost-effective choice over the long term, avoiding repeated filling replacements.