Dental crowns, often called “caps,” are custom-made coverings that restore a damaged tooth’s shape, size, and strength. They fit over the entire visible portion of a tooth. Among various materials, metal crowns are known for their robust characteristics and specific dental applications.
The Purpose of Metal Dental Crowns
Metal dental crowns serve several purposes due to their exceptional strength and durability. They are frequently used to restore teeth that have suffered severe damage from decay or fracture, encapsulating the entire tooth to provide comprehensive protection. This protective function also extends to weak teeth, preventing them from breaking apart, or holding together segments of a cracked tooth.
Metal crowns are also employed to cover and support a tooth with a substantial filling, especially when much of the natural tooth structure is compromised. Following a root canal procedure, a metal crown is often placed to shield a brittle tooth from potential fractures.
Metal crowns also function as anchors, providing stable support for dental bridges, which replace one or more missing teeth. Their ability to withstand significant chewing pressure makes them suitable for back teeth like molars and premolars, where chewing forces are highest. This resilience ensures the crown can endure the demands of daily oral function without easily chipping or breaking.
Types of Metal Crowns and Their Composition
Metal dental crowns are made from various alloys, each offering distinct properties based on their composition. Gold alloys are a traditional choice, typically composed of gold mixed with other metals such as copper, platinum, palladium, or silver.
These alloys are known for their malleability, allowing for a precise fit, and their biocompatibility, meaning they are well-tolerated by the body with a low risk of allergic reactions. Gold alloys also resist corrosion and wear, and they are notably gentle on opposing natural teeth.
Base-metal alloys, such as those containing nickel-chromium or cobalt-chromium, are another category. These alloys are highly strong and hard, offering significant resistance to wear and fracture. They also tend to be more cost-effective compared to gold alloys.
Porcelain-fused-to-metal (PFM) crowns combine the strength of a metal substructure with the aesthetics of a porcelain outer layer. The metal base provides the necessary durability and structural support, while the porcelain layer is color-matched to natural teeth, offering a more natural appearance than all-metal crowns. PFM crowns offer a balance between strength and aesthetics, though the metal substructure can sometimes be visible at the gumline if recession occurs.
Caring for Your Metal Crown and Longevity
Proper care for a metal dental crown involves maintaining consistent oral hygiene practices, similar to caring for natural teeth. Regular brushing, at least twice daily with fluoride toothpaste and a soft-bristled toothbrush, is important to prevent plaque buildup around the crown and the surrounding gum tissue. Daily flossing is also essential to remove food particles and plaque from between teeth and around the crown’s margins. Using an antibacterial mouthwash can further help reduce bacteria.
While metal crowns are recognized for their durability, they are not impervious to damage. Their lifespan can be influenced by several factors, including individual oral habits and overall oral health. Habits like teeth grinding (bruxism) or clenching can exert excessive force, potentially wearing down the crown or the underlying tooth structure, and a nightguard may be recommended to mitigate this. Avoiding very hard, crunchy, or sticky foods can also help prolong the crown’s life by preventing chipping or dislodgement.
With diligent care and regular dental check-ups, metal crowns can last for many years. While average lifespans often range from 10 to 15 years, some metal crowns, particularly those made from gold alloys, can last for 20 years or even several decades. Consistent professional dental examinations allow for early detection of any issues, ensuring the crown continues to function effectively and remains in good condition.