Understanding Dental Crown Materials: A Comprehensive Guide

When it comes to dental care, a crown can make a difference. It not only improves the appearance of a tooth but also protects it from further damage, restoring its natural function and look. With a range of materials available, from traditional metals to modern ceramics, let’s explore the options and find out what each has to offer.

What are dental crowns?

Dental crowns are custom-made covers or caps that is designed to enclose a prepared tooth. It aims to restore the tooth's shape, size, strength and appearance. They play an important role in dentistry by:

• Protecting a weakened tooth that is decayed, broken or damaged
• Covering a tooth that has a large filling
• Holding a fixed dental bridge in its place
• Covering misshapen teeth
• Covering severely discoloured teeth
• Enclosing a dental implant

What are the types of dental crown materials?

There are several types of materials used for dental crowns, each with its own set of advantages and disadvantages. Let's explore each one of them!

1) Porcelain-Fused-to-Metal (PFM) Crowns

If you’re considering dental crowns, you might come across porcelain-fused-to-metal (PFM) crowns. They’ve been a popular choice for many years and for good reason. Studies show they have a 94% success rate over a decade, which speaks volumes about their reliability. The PFM dental crown combine two materials to give you both strength and a natural look.

• Metal Framework (Inner Layer): The inside of the crown is made from metal, which gives it the strength to handle everyday chewing and grinding. This metal makes the crown durable and tough, perfect for back teeth where the pressure is higher.
• Porcelain Outer Layer: The outside is covered with porcelain, which is designed to match the colour of your natural teeth. 
  

Pros of PFM crowns:

• Strong and durable
• Natural-looking appearance

Cons of PFM crowns:

• Sometimes, a dark line can appear at the gum line where the metal meets the porcelain. This can be more noticeable if your gums recede over time, which might not be ideal for everyone. Read more about it here.
• The porcelain might chip or break if the bond with the metal weakens over time. This can affect both the look and function of the crown. Click here to read about what to do when your crown chips.
• Getting a PFM crown means removing a bit more of your natural tooth to make space for the metal and porcelain. This can be a bit more invasive compared to other crown options.

2) All-Ceramic Crowns

All-ceramic crowns, also known as all-porcelain crowns, are a popular choice for many patients because they don’t have any metal components, making them a good option for those seeking a natural look. Two main types of all-ceramic crowns are Zirconia crowns and Lithium Disilicate crowns, each with its own unique properties.

Zirconia Crowns

Zirconia crowns are made from zirconium dioxide, a ceramic known for its strength. These crowns are often milled from a single solid block, which gives them impressive durability and makes them nearly resistant to chipping or cracking. This makes them a favourable choice for areas that experience a lot of pressure, such as the back teeth.

Zirconia crowns can also be adjusted to closely match the colour of natural teeth. However, they tend to be somewhat opaque and lack the natural translucency of real teeth, hence imparting a less life-like look.

Lithium Disilicate Crown

Lithium Disilicate crowns are made from a type of ceramic consisting of a glass matrix. This unique composition gives them translucency and natural light-reflecting properties, making them look very much like real teeth.

While they are quite strong, they are not as durable as zirconia crowns. Research shows that Lithium Disilicate crowns have about 40% of the strength of zirconia, which makes them more prone to damage under heavy pressure. Therefore, they are a great choice for front teeth where appearance is particularly important.

Pros of All-Ceramic crowns:

• Best colour match with natural teeth
• No metal allergies

Cons of All-Ceramic crowns:

• More expensive than PFM crowns

3) Gold Crowns

Gold crowns have been used in dentistry for a very long time and were once extremely popular. These days, they aren't as common because they don't look as natural, and the price of gold keeps going up! Despite this, gold crowns are still a great option for many people because they’re incredibly durable. They can handle a lot of pressure from chewing and are unlikely to crack or chip.

A common question patients ask is, "How much gold is actually in a gold crown?" The answer varies depending on the specific dental needs. Gold dental crowns are usually mixed with other metals to improve their strength and durability. As a rule of thumb, the higher the gold content, the better the crown will fit and function—and the higher the cost.

Pros of Gold crowns:

• Very durable
• Gentle on neighbouring teeth
• Biocompatible

Cons of Gold crowns:

• Not tooth-coloured
• Can be costly

4) All-Metal Crowns

All-metal crowns are made from alloys that don’t include gold or other noble metals. Instead, they use metals like nickel and chromium, giving them a distinct “steel” or "metallic" look. This is why they’re generally not used for front teeth.

All-metal crowns are tough and can handle intense pressure from chewing and grinding. A major benefit of these crowns is that they require less removal of the natural tooth during preparation. Their strength allows them to be made thinner, which helps preserve more of your original tooth structure.

Pros of All-Metal crowns:

• Very durable
• Less tooth removal required
• Cost effective (cheaper than the above options)

Cons of All-Metal crowns:

• Not tooth-coloured
• Some people may be allergic or sensitive to certain metals, such as nickel

5) Acrylic Temporary Crowns

The four types of crowns discussed above are all permanent options that are designed to last for many years. However, there are times when temporary crowns are needed. These temporary crowns, usually made from acrylic, are meant to be used for a short period while you wait for your permanent crown, which typically takes about two weeks to make.

Acrylic crowns are easy to shape and adjust and can be created right in the dental office. Because they are only temporary, they aren’t as durable or as closely matched to your natural tooth colour as permanent crowns. Nevertheless, they do a good job protecting your tooth. Keep in mind that they might come with additional costs.

At Dental Designs, we’ve made things easier by offering Same Day crowns. With our in-house dental lab, we offer metal-free crowns that are created on the same day as your tooth preparation, so you won’t need to wait two weeks or use a temporary crown, saving both time and money!

Pros of Temporary crowns:

• Protects the prepared tooth
• Allows you to eat and speak normally
• Prevents tooth sensitivity

Cons of Temporary crowns:

• Not as durable as permanent crowns
• May not fit as precisely
• Can be less aesthetically pleasing
• More prone to fractures

How do I choose the best material for my dental crown?

• The location of the tooth
• The amount of natural tooth remaining
• Your personal preference
• Any allergies you may have
• Cost considerations

Depending on these factors, your dentist will help you decide which material is best for your situation. Read more about it here. 

Related Articles

• Pros and Cons of Dental Crowns: Are Dental Crowns Necessary?
• How Are Dental Crowns Made: A Dentist in Singapore Explains (2024)

The Role of Dental Crowns in Root Canal Treatment

Root canal treatment often requires the placement of a dental crown to protect and restore the tooth’s function. A crown is a tooth-shaped cap that covers the affected tooth, providing strength and durability. Dental crown procedures are typically performed after a root canal to ensure the tooth remains intact. These crowns can be metal-free, offering a more natural appearance, and are custom-made in a dental laboratory to fit perfectly. Learn more about why you need a dental crown after a root canal treatment, here.

In some cases, a dental bridge might be used in conjunction with a crown procedure to replace missing teeth. Regular dental visits are essential to ensure that both the permanent crown and any dental bridge remain in good condition.

Conclusion

Understanding the various dental crown materials and their benefits can help you make an informed decision about your dental care. Whether you need a crown for a front or back tooth, there's a material that can meet your needs for strength, durability and appearance. Always consult with your dentist to find the best option for your specific situation.

Ready to book a dental appointment with us? Simply drop us a message here and will be happy to assist!

References

1. Makhija SK, Lawson NC, Gilbert GH, Litaker MS, McClelland JA, Louis DR, Gordan VV, Pihlstrom DJ, Meyerowitz C, Mungia R, McCracken MS; National Dental PBRN Collaborative Group. Dentist material selection for single-unit crowns: Findings from the National Dental Practice-Based Research Network. J Dent. 2016 Dec;55:40-47. doi: 10.1016/j.jdent.2016.09.010. Epub 2016 Sep 28. PMID: 27693778; PMCID: PMC5125852.
2. Warreth A, Elkareimi Y. All-ceramic restorations: A review of the literature. Saudi Dent J. 2020 Dec;32(8):365-372. doi: 10.1016/j.sdentj.2020.05.004. Epub 2020 May 29. PMID: 34588757; PMCID: PMC8461086.