When it comes to dental work, crowns are one of the most common ways to restore damaged teeth. A crown is a cap that fits over a tooth to protect it or improve its appearance. While there are many types of crowns available, zirconia crowns have become one of the most popular options in recent years. They are strong, durable, and look very natural. But what exactly are zirconia crowns, and how do they compare to other types of crowns, like PFM crowns? Let’s break it down.
What Are Zirconia Crowns?
Zirconia crowns are made from zirconium oxide, a tough, white ceramic material. They are one of the strongest types of tooth-colored restorations available today. Zirconia has been used in medicine since the 1970s, but it wasn’t until the early 2000s that it became a popular choice in dentistry.
There are two main types of zirconia crowns:
Full-Strength Zirconia – This type is made for situations where the tooth needs maximum strength. It’s perfect for back teeth that deal with a lot of pressure when chewing.
Aesthetic Zirconia – This type is designed for teeth that are more visible, like the front teeth. It’s not as strong as full-strength zirconia but looks more natural.
Zirconia crown is created by milling a solid block of zirconia into the shape of a crown. Since they are made from one material, they are very strong and can be used for many types of dental problems.
What Are PFM Crowns?
Before zirconia crowns, PFM (porcelain fused to metal) crowns were one of the most common types of crowns. These crowns are made by layering porcelain over a metal base. The metal gives the crown strength, while the porcelain gives it a natural tooth-like appearance.
PFM crowns have been around for a long time, since the 1950s. They were a great solution when there weren’t many options for tooth-colored materials. The metal inside these crowns can sometimes cause the gums to look dark, and the porcelain can chip or crack over time, but they are still used in certain situations.
Key Differences Between Zirconia and PFM Crowns
The main difference between zirconia crowns and PFM crowns is the materials they are made from. Zirconia crowns are made from a single material, zirconium oxide, while PFM crowns are made from two materials: metal and porcelain.
Because zirconia crowns are made from one material, they tend to be much stronger and less likely to chip or break compared to PFM crowns. PFM crowns, on the other hand, have some weaknesses due to the fact that the metal and porcelain expand at different rates. This can cause the porcelain layer to crack or break off over time.
Zirconia crowns also don’t have the same issues with dark lines at the gum line that PFMs sometimes have. Since zirconia is white and translucent, it looks much more natural in the mouth.
However, PFM crowns are still useful in certain situations. For example, if there isn’t enough vertical space for a zirconia crown or surrounding restorations are also of PFM or cost is a concern, a PFM might be a better choice.
Advantages of Zirconia Crowns
- Strength and Durability: Zirconia crowns are incredibly strong and can last a long time. They are perfect for teeth that need to handle a lot of pressure, such as back molars.
- Natural Appearance: Zirconia is very tooth-like in appearance, especially the newer esthetic versions. They blend well with natural teeth and do not cause dark lines at the gums like PFMs sometimes do.
- No Metal Allergies: Some people are allergic to metals used in PFM crowns. Since zirconia crowns are made from a ceramic material, they are safe for people with metal allergies.
When to Use Zirconia Crowns
Zirconia crowns are a great option for a variety of dental situations. They can be used for:
Single crowns for teeth that are cracked, decayed, or worn down.
Bridges for replacing missing teeth.
Veneers, inlays, and onlays for smaller cosmetic repairs.
Implant crowns to replace missing teeth.
Zirconia crowns are especially beneficial for people who need durable and strong restorations. They’re also a good choice for patients who have metal allergies.
When to Use PFM Crowns
While zirconia crowns have many advantages, there are still situations where PFM crowns are the better choice. For example, if there isn’t enough space to fit a thick zirconia crown, a PFM might be a better option because it can be made thinner. Also, if a tooth has had a root canal and is very dark, a PFM crown might be used because the metal base helps prevent shadows from showing through the porcelain.
PFM crowns can still be a good choice for teeth that are not exposed to as much pressure, like front teeth. They are also often used for patients who want a more cost-effective option.
Advantages of PFM Crowns
- Durability: While not as strong as zirconia, PFM crowns are still very durable. The metal core gives them strength, which makes them last a long time.
- Cost: PFM crowns are often less expensive than zirconia crowns, making them a good choice for patients on a budget.
- Better for Certain Cases: PFM crowns can sometimes be a better choice for certain types of dental work, such as large bridges or teeth that need more support.
Disadvantages of PFM Crowns
- Less Natural Appearance: PFM crowns are made with metal, so they can sometimes cause dark lines at the gums or look less natural, especially for front teeth.
- Potential for Chipping: The porcelain layer on PFM crowns can chip or crack over time, especially if you grind your teeth or bite down on hard foods.
Conclusion: Zirconia vs PFM Crowns
Zirconia crowns are becoming more and more popular because they are strong, natural-looking, and durable. They are a great option for most dental patients, especially those who need a crown for back teeth or who have metal allergies. On the other hand, PFM crowns still have a place in dentistry, especially when there isn’t enough space for a thick zirconia crown or when cost is a concern.
When it comes to choosing between zirconia and PFM crowns, your dentist will help you decide which is best for your specific needs. Both options have their advantages, and the right choice will depend on factors like the location of the tooth, the amount of space available, and your overall dental health.
If you’re considering a crown, ask your dentist about zirconia and PFM options to see which one will give you the best results for your smile!