Dental crowns play a crucial role in restoring the function, appearance, and structure of damaged teeth. Nevertheless, like all dental restorations, crowns have a finite lifespan. Let’s explore the various types of dental crowns, the factors that influence their longevity, and the maintenance required to maximize their durability, which is vital to ensuring a healthy and confident smile.
Types of Dental Crowns
- Porcelain Crowns
Mimic the translucency and light-reflecting properties of natural teeth, making them indistinguishable. Even so, porcelain crowns are more prone to chipping or cracking. They are best suited for the front teeth.
Pros: Aesthetic appeal, great for front teeth
Cons: Less durable, more expensive than metal-based options
- Ceramic Crowns
Used for individuals with metal allergies. Ceramic crowns, due to their lifelike appearance, are also suitable for restoring front teeth. Although stronger than porcelain, they may not withstand heavy chewing forces.
Pros: Metal-free, natural appearance, suitable for metal allergies
Cons: Prone to wear and chipping under pressure
- Metal Crowns (Gold, Palladium)
Gold crowns have been used for decades due to their remarkable strength and biocompatibility. While not aesthetically pleasing, metal crowns are resistant to chipping or breaking. They are used for teeth that endure heavy biting forces.
Pros: Durable, minimal wear to opposing teeth, long-lasting
Cons: Not visually appealing, expensive due to the cost of precious metals
- Porcelain-Fused-to-Metal (PFM) Crowns
PFM crowns are versatile and can be used for front and back teeth. Still, the porcelain layer may chip, and the metal underlay can become visible near the gumline as gums recede.
Pros: Strong, aesthetical, suitable for front and back teeth
Cons: Porcelain may chip, metal may surface over time
- Zirconia Crowns
Made from zirconium dioxide, zirconia crowns are strong and can be milled to a precise fit using digital technology. They offer a natural appearance and are biocompatible, reducing the possibility of irritation or allergic reactions.
Pros: Extremely strong, biocompatible, natural-looking
Cons: Can be more opaque than porcelain, higher cost
- Resin Crowns
Made from composite resin, these crowns match the hue of natural teeth. However, resin crowns are prone to wear and staining and may need to be replaced more often. They are used for temporary restorations while waiting for a permanent crown to be fabricated.
Pros: Affordable, natural appearance
Cons: Prone to wear and staining, not as durable, often used temporarily
Average Lifespan of Dental Crowns
- Porcelain Crowns: Porcelain crowns last 10 to 15 years. They tend to last longer because they are placed on the front teeth, which face less pressure. Their susceptibility to chipping and wear from biting or grinding can reduce longevity.
- Ceramic Crowns: Similar to porcelain, ceramic crowns can last between 10 and 15 years. They offer improved strength over porcelain but can still chip under extreme pressure.
- Metal Crowns (Gold, Palladium): Metal crowns are known for their durability, lasting 15 to 20 years. In some cases, metal crowns last a lifetime. These crowns are resistant to wear and seldom need replacement unless the tooth deteriorates.
- Porcelain-Fused-to-Metal (PFM) Crowns: PFM crowns last between 10 and 15 years. The metal base provides durability, while the porcelain exterior can chip or wear down, especially when subjected to heavy chewing forces.
- Zirconia Crowns: These are among the most durable options, lasting 15 to 20 years on average. With advanced fabrication techniques, zirconia crowns can last even longer due to their high resistance to chipping and cracking.
- Resin Crowns: Resin crowns are often a short-term solution, lasting 5 to 10 years. Compared to other materials, they are more prone to wear, discoloration, and damage.
Factors Affecting Dental Crown Longevity
- Material of the Crown
Metal crowns are durable and resistant to wear, while porcelain and ceramic crowns, though aesthetically pleasing, are more prone to chipping or cracking. Zirconia crowns strike a balance between aesthetics and strength. Resin crowns, in contrast, are less durable and may need to be replaced more frequently. - Placement of the Crown
Crowns on molars, which bear the brunt of chewing forces, are subject to more wear and tear. As a result, crowns on back teeth, especially those made from porcelain or ceramic, may wear down faster. Metal or zirconia crowns are often recommended for molars due to their durability under heavy biting pressure. - Oral Hygiene Habits
Brushing and flossing prevent plaque and bacteria buildup, reducing the risk of decay at the crown’s margins. Poor oral hygiene can lead to gum disease or cavities, both of which shorten the life of the crown by affecting the underlying tooth structure. - Teeth Grinding (Bruxism)
Excessive pressure and friction can cause crowns, especially porcelain and ceramic crowns, to chip, crack, or wear down. Individuals who grind their teeth may benefit from wearing a nightguard to protect the crowns and natural teeth from damage. - Diet
Eating hard or sticky foods, such as ice, hard candies, or chewing gum, can increase the possibility of chipping or dislodging a crown. Acidic foods and beverages can erode the cement that holds the crown in place. A balanced diet that avoids excessive chewing strain can preserve the integrity of the crown. - Gum Health and Recession
If gum disease develops, the gums recede, exposing the edges of the crown or the underlying tooth, which increases the risk of decay or infection. Maintaining healthy gums through dental visits and proper oral hygiene is critical to ensuring the crown remains secure and functional. - Quality of Crown Placement
A poorly fitted crown may leave gaps between the crown and the tooth, making it susceptible to decay, loosening, or failure. Precise fitting and secure crown cementing are crucial to ensuring its longevity. - Dental Check-Ups
Routine dental visits are essential. During these visits, the dentist can assess the crown’s condition, identify signs of wear or damage, and take preventive action. Regular cleanings also maintain gum health, reducing the risk of complications.
Dental Crown Maintenance and Care
Brushing twice daily and flossing prevent decay and gum disease. Using an antibacterial mouthwash can further protect the area from plaque buildup. Avoid habits like biting fingernails or chewing ice.
If a client grinds their teeth, wearing a nightguard is essential. Avoiding hard or sticky foods is vital for individuals with porcelain or ceramic crowns.
Signs of Dental Crown Wear or Failure
- Chips or cracks in the crown surface
- Loose fit or sensing the crown is shifting
- Increased sensitivity to hot or cold foods
- Pain or discomfort when chewing
- Gum recession around the crown, which may expose the underlying tooth
Impact of Oral Hygiene on Crown Lifespan
Brushing twice a day with fluoride toothpaste protects the underlying tooth from decay, while flossing removes food particles and plaque from around the crown’s margins. Without proper care, decay can form at the base of the crown, leading to crown failure. Dental cleanings are also important, as they remove plaque and tartar that can contribute to gum disease.
The Role of Dental Check-Ups for Crown Durability
Check-ups are crucial. The dentist can assess the crown for wear, looseness, or decay. Professional cleanings prevent gum disease. The dentist can take preventive measures, such as adjusting the crown or recommending a nightguard for bruxism.
Consequences of Not Replacing a Failed Crown
If a failed dental crown is not replaced, it can lead to several complications. The exposed tooth may develop decay or infection, requiring a root canal or extraction. Also, a broken or loose crown can affect the bite. Delaying crown replacement increases the risk of tooth loss or invasive dental procedures.
Cost and Insurance Considerations for Dental Crowns
Crowns made from precious metals are more expensive. Porcelain and zirconia are more costly than resin crowns due to their durability and aesthetic benefits.
Most dental insurance plans cover a portion of the cost. Check with your provider to understand the benefits and if the insurance covers certain materials or limits reimbursement for cosmetic procedures.
Dental Crown Warranty
Some dental offices offer guarantees on crowns, covering repairs or replacement within a certain time frame. These warranties range from a few years to lifetime coverage, depending on the practice and the type of crown. Warranties cover defects in the crown or issues related to fit but may not cover damage caused by accidents or improper care.
How to Extend the Life of a Dental Crown
- Maintain good oral hygiene by brushing and flossing
- Avoid hard or sticky foods that can damage the crown
- Wear a nightguard if you grind their teeth
- Attend dental check-ups and cleanings
- Avoid using teeth to open packages or bite non-food objects
Crown Replacement Process
If a crown fails or becomes damaged, the replacement process typically involves the following steps:
- Examination: The dentist assesses the crown’s condition and determines whether replacement is necessary.
- Removal of the Old Crown: The old crown is removed, and decay or damage to the underlying tooth is treated.
- Impression: A new impression of the tooth is taken to fabricate the replacement crown.
- Temporary Crown: A temporary crown may be placed while the new one is created.
- Placement of the New Crown: Once the new crown is ready, it is bonded to the tooth.
Risks Associated with Worn-Out or Damaged Crowns
- Tooth decay under the crown
- Gum disease due to bacteria accumulation
- Infection if the tooth is exposed
- Fracture or breakage of the underlying tooth
- Bite misalignment from a loose or damaged crown
Technological Advancements in Dental Crown Fabrication
Computer-aided design and manufacturing (CAD/CAM) allow for the precise fabrication of crowns. New materials, like monolithic zirconia, offer superior strength and a natural appearance. Same-day crown technology, such as CEREC, allows individuals to receive crowns in a single visit, improving convenience.
Conclusion
Dental crowns can last many years, providing essential protection and functionality. Factors such as the material used, oral hygiene, and dental check-ups all play a significant role. By understanding how to care for a crown and recognizing the signs of wear or failure, individuals can enjoy the benefits of their restoration for many years.
