What Are Dental Crowns Made Of? Choose Which One To Get

Dental crowns and restorative are protective covers often placed over treated teeth when fillings don’t suffice. These crowns are not all the same and are available in various materials. If you are wondering which dental crown type to go with, let us help you. 

Need For Dental Crowns

To opt for a suitable dental crown material, it is essential to understand the role that these dental prosthesis play. There are several functions that dental crowns can perform, depending upon the condition they are placed in. Some of these roles are as follows. 

Protection

A treated tooth is often rendered weak and susceptible to breaking. Dental crowns are usually placed over such teeth to protect them from cracking oR holding together an already cracked tooth. 

Restoration

A tooth that is severely decayed tooth loses its crown and, therefore, its functionality. Placing a cap over the treated remains of the tooth can help it restore both its structure and function. 

Bridge

A dental bridge is another dental prosthesis that helps replace a missing tooth by creating a bridge. The two teeth adjacent to the edentulous area are covered with dental crowns and used as anchors for the bridge. 

Implant

A dental implant is a type of tooth replacement where an implant is inserted into your jaw to act as the root of a natural tooth. Meanwhile, a dental crown is placed on the implant to complete the prosthetic unit and restore function. 

Root Canal Treatment

A tooth that has undergone root canal treatment is at a greater risk of being infected again if left as is. To avoid re-infection and contamination, the tooth is capped with a dental crown to protect it from harmful substances that could lead to tooth decay. 

Aesthetics

Several factors can cause our teeth to stain or deform permanently. In such cases, the affected teeth, especially those visible and in front, are capped with a dental crown to restore the aesthetic aspect of the dentition. 

Process Of Getting Dental Crowns

The complete process of getting a dental crown can vary from case to case. However, you will undoubtedly undergo one of two procedures—either a same-day procedure or one that spans several days. 

Multi-Day Procedure

While getting a traditional crown, you need to visit your dentist at least twice. Before getting a dental crown, your dentist must ensure cavities or active oral health conditions are taken care of. The dental crown procedure can begin only once all has been taken. 

Examination and Recording

On your first visit, the tooth is examined, and its dimensions are recorded using X-rays and moulds. This examination allows your dentist to get a better idea of the amount of healthy tooth structure they are working with. 

Tooth-Cutting

The outer layer of your tooth is cut and filed. This cutting is done to make enough space for the dental crown to sit on your tooth. How much of your tooth gets cut depends upon the type of dental crown being placed. 

Impression

Another impression is recorded of mouth once the cutting is done. This impression is what the final permanent crown will be based on. 

Temporary Crown

The permanent crown will take weeks before it is ready. Therefore, a temporary crown will be placed over the tooth to protect it. 

Final Fitting

Once the permanent crown is ready, your dentist will call you again to fit them in. Your temporary crowns will be removed and replaced with permanent ones. 

Same-day Procedure

In a same-day procedure, you no longer need to wait with a temporary crown. This advanced method uses CAD/CAM machines that generate 3D crowns within hours. The process is, however, quite simple.

The dentist starts by taking digital scans of your mouth, which are fed into the CAD/CAM machine. This machine then generates a crown that can be permanently cemented onto your tooth immediately. The immediate availability of the permanent crown eliminates the need for a temporary one. 

What Are Dental Crowns Made Of?

Dental crowns can vary in terms of the materials used for their production. Each of these materials provides characteristic features and pros and cons. 

Typically, there are five different types of crowns based on material. These types are as follows. 

1) Metal Crown

In the past, gold crowns were very famous. However, their use today is minimal. This is because of two main reasons. The first one is their cost, which weighed very heavy on the people’s pockets, given that gold is a noble metal.

The second and another important reason for their decline is aesthetic. The colour of gold differs significantly from that of a natural tooth. With the development of more natural-looking and affordable dental crowns, gold crowns remained for only those who wished to use them as an expression of wealth.

Unlike gold dental crowns, other metal crowns are still frequently used. Like Gold crowns, they also come with the feature of being different from a natural tooth in colour. However, these crowns are less expensive.

Compared to other types of dental crowns, these are the strongest, given their all-metal composition. These crowns are made of dental alloys, blends of two or more metals. The properties obtained from mixing metals create a combination of properties desired from each metal included.

Metal crowns are resilient and resist wear, even under a comparatively more significant amount of force. This makes it the perfect option for out-of-sight molars, the site for the main chewing in our mouth. Here, the metal crown’s ability to withstand forces allows it to last longer than other materials in the same conditions, and the colour of it doesn’t matter since the tooth isn’t visible.

One of the most significant advantages of metal crowns is that they require a smaller portion of your tooth to be cut off during tooth cutting for crown placement. This allows you to retain the maximum natural tooth structure, which is always preferable in dentistry. 

2) All Ceramic/ All Porcelain Crown

Ceramic is hard heat-resistant material that is inorganic and nonmetallic. Traditional ceramics have three main components: clay, silica and feldspar. Porcelain is a specific type of ceramic. Therefore, not all ceramic crowns are porcelain crowns.

One of the most significant advantages of a ceramic crown is that it can be matched to a natural tooth very closely. The natural structure of the tooth provides it with a translucent exterior that reflects light in a particular manner. Porcelain crowns mimic this property of teeth, in particular, and look very similar to natural teeth and blend right in. This allows for a discreet restoration that is also aesthetically pleasing.

Ceramic dental crowns have one significant disadvantage: they wear down the teeth opposing them. Furthermore, they also require more tooth structure to be removed for their placement due to the thickness of the material needed to retain its strength and rigidity.

Ceramic crowns also fracture faster than metal crowns. This property makes them too weak to bear biting and chewing forces. Therefore, ceramic crowns are a better option for capping anterior teeth as they take less pressure.

Full ceramic crowns can be manufactured in two ways. 

Dental Laboratory Produced Crown

In this process, the dental lab uses different porcelains, each with a different shade and translucency. These porcelains are used in multiple layers around the crown. Production of crowns in this manner gives them an excellent colour match and lifelike feel. 

CAD/CAM Machine-Produced Crown

Unlike laboratory-made crowns, these ceramic crowns are produced by machines as a uniform block. The lack of layers in these crowns removes the translucency that gives laboratory crowns a lifelike feel. 

3) Zirconia Crowns

There is a wide variety of ceramic crowns available today. Zirconia crowns are known to be the strongest and the hardest of them.

Zirconia falls under the category of glass ceramic and is crystal in nature.

While the colour of Zirconia crowns can be matched with that of a natural tooth crown, it lacks the translucency of porcelain that gives it a close-to-real feel. However, Zirconia is often used to form the core of the crown, with porcelain layered on top for optimal aesthetics.

The inner surface of dental crowns is usually etched (roughened using chemicals) before being cemented to the tooth to provide a better bond. However, given the hard nature of Zirconia, it cannot be etched like other dental materials used for crowns. Zirconia has to be sandblasted to create a rough surface texture, and then a special bonding agent is used. 

4) Porcelain-Fused-to-Metal Crown (PFM)

As the name suggests, porcelain-fused-to-metal crowns consist of a combination of metals with porcelain. The inner core of the crown is made out of a metal alloy and is bonded with the tooth. Over this alloy base, porcelain is layered and bonded, giving the crown its proper tooth-like structure and colour. These crowns have been used for over 50 years and are known to work very well.

PFM crowns combine the desirable qualities of both materials and give us the best of both worlds. The metal core adds strength to the unit, while the porcelain layering hides the silver of the metal and provides a natural tooth-like look.

Since metal and porcelain are very durable as dental materials, PFM crowns possess great longevity and are known to last several years. Furthermore, they are a lot more affordable than other types of crowns while providing better benefits.

However, as the gum line recedes in later ages, the underlying metal may become visible at the edges, which can be aesthetically displeasing.

All the different types of dental crowns discussed above are permanent crowns. These crowns are not meant to come off once placed and last for a long time. Sometimes, getting a dental crown requires wearing a temporary one. This is when your teeth have been cut for the permanent crowns, but you have to wait till the permanent crowns are manufactured.

Leaving the cut-down teeth exposed and unprotected may lead to several consequences. Furthermore, chewing with such teeth would also be a tough job, making eating harder. For this reason, temporary crowns are placed over them, so you may go about your day normally till the permanent ones are ready to be placed. 

A temporary crown can be of two types. These types are as follows. 

Resin Crown

All resin crowns are made of composite resin material, a combination of different plastics that match the colour of natural teeth. Some standard resins used to make these crowns include silicon dioxide resin, Polymethyl Methacrylate resin, or acrylic polymer resin.

Resin crowns are commonly used as a temporary fix, safeguarding the tooth or filling until the permanent crown can be made. This is because they wear down quickly and do not withstand biting and chewing forces well over time.

They’re also a metal-free option to stainless steel temporary crowns and come in different shades to better match the colour of natural teeth–which patients may prefer for aesthetic reasons.

They work best on your front teeth if you want to use them as permanent crowns. They can also be used instead of a straight filling since they go around the entire tooth surface, making them stronger and more durable. 

Stainless Steel Crown

Stainless steel crowns are mainly used as a temporary measure for adult teeth, protecting the tooth or filling until the permanent crown can be made. However, these crowns act as permanent crowns for primary or baby teeth, coming out only once the teeth fall out.

Amongst pediatric dental practices, stainless steel crowns are famous because they take fewer visits to be fitted and cemented, and they’re a more affordable choice for a baby tooth that will be lost eventually. 

Final Word

When it comes to picking a dental crown, the options are plenty. The best choice for you depends upon your needs and requirements. A consultation with your dentist will be beneficial in figuring out what will work best for you. Call us now on (02) 8007 6727.

Note: Any surgical or invasive procedure carries risks. 

References

Everything You Need To Know About Getting A Dental Crown
https://www.healthline.com/find-care/articles/dentists/dental-crown

Dental Crown Procedure
https://www.healthdirect.gov.au/dental-crown-procedure

Dental Crowns
https://www.webmd.com/oral-health/guide/dental-crowns

Bridges & Crowns
https://www.colgate.com/en-us/oral-health/bridges-and-crowns/different-types-of-dental-crowns#

What Are The Materials Used To Make Dental Crown?
https://www.preciseceramic.com/blog/materials-used-to-make-dental-crown/