Zirconium dioxide (commonly known as zirconium) is a ceramic material widely used in dentistry. Its durability, compatibility with body tissues (biocompatibility), and aesthetic appearance close to that of natural teeth make it a preferred choice. Due to its high strength, it is sometimes referred to as ‘ceramic steel.’ This material, which does not contain a metal substructure, allows for natural-looking permanent restorations to be made on both front and back teeth.

Average lifespan of Zirconia crowns?

Zirconia crowns are one of the most durable materials among dental ceramics. Their average success rate over 10-15 years is quite high. However, this period is directly related to care, oral habits, and the quality of application. With good oral care and regular dental check-ups, your zirconia crowns can be used without any problems for decades.

Factors affecting the lifespan of zirconia crowns

There are many factors that affect the lifespan of a zirconia crown. The most important of these factors are as follows:

Type of zirconia crown

Crown made entirely of zirconia (monolithic):

It is made from a single piece of zirconia, carved with a milling machine. This is the strongest option. It is particularly preferred for back molars, where chewing force is greatest. As strength was the priority in the past, it used to be slightly more opaque aesthetically, but the new generation of full zirconia crowns now looks quite natural.

Porcelain-coated zirconia:

Porcelain layers with light transmission similar to natural teeth are added to a thin but strong zirconia framework. This provides the highest level of aesthetic results. However, in very rare cases, such as excessive impact or teeth grinding, there is a slightly higher chance of a small crack forming in this porcelain layer compared to a single piece of zirconia. With today's bonding techniques and materials, this risk is significantly minimized.

Zirconia and bonding qualities

Zirconia has a smooth structure, so it used to only bond mechanically. However, thanks to special surface treatments and modern, strong adhesives, it can now bond to the tooth much more strongly, both mechanically and chemically.

The greatest benefit of this proper bonding is that it makes it nearly impossible for saliva or bacteria to seep in from the edge of the crown. If this seepage is not prevented, your own tooth beneath the crown may begin to decay again, which is one of the most common reasons for the crown's lifespan to end.

Occlusion adjustment

• When the crown is fitted, when your dentist says ‘bite down gently,’ what they are actually doing is adjusting the bite. The alignment of the crown with the other teeth (occlusal height) must be perfect. Your dentist makes very fine adjustments to ensure that the crown closes perfectly with the other teeth.
• If the crown is too high, meaning it makes contact before the others, excessive pressure is placed on it with every bite or clench. Over time, this can lead to cracks in the crown itself or its porcelain surface, pain and loosening in the tooth the crown supports, and even problems with your jaw joint.
• A well-executed bite adjustment is the key to ensuring your crown remains durable and trouble-free.

Teeth grinding

This is one of the greatest threats to all dental restorations, including zirconia.

• Performed unconsciously at night or due to daytime stress, this action can exert pressure up to 10 times greater than normal chewing force.
• Even though zirconia is resistant to these forces, the underlying natural tooth structure or implant can be damaged by this constant excessive load. Furthermore, wear or tiny cracks may form on the surface of porcelain-coated zirconia.
• The solution is a night guard. This is a transparent, thin plate that your dentist will custom-make for you. It prevents your teeth from coming into direct contact with each other and causing damage, distributes the pressure, and protects both your crown and your own teeth.

Gum recession

Over time, gums may recede slightly due to age or gum disease. This recession can expose the edge of the crown. Food debris can accumulate in the exposed spaces when gums recede, which can cause decay in your own tooth beneath the crown and shorten the life of the restoration. Gum recession causes two problems:

Aesthetic problem: The crown-tooth junction becomes visible. This can sometimes appear as a dark line (particularly noticeable in older porcelain-metal crowns, less so in zirconia).

Hygiene issue: This exposed area becomes a favorable region for bacterial plaque accumulation. It becomes difficult to clean and can both compromise your gum health and initiate new decay around the edge of the crown.

Good oral hygiene is the best way to prevent gum recession

Crown support (tooth or implant)

The foundation on which crown is placed is very important. There are two main ways to ensure this:

Natural tooth support:

The crown is bonded onto a reduced version of your own tooth. Whether the tooth is alive or has undergone root canal treatment affects the situation. Living teeth are more flexible and act as a buffer against impact. Root canal-treated teeth, however, can become more brittle over time. For this reason, crowns placed on root canal-treated teeth are usually extended to the gum line to provide additional support.

Implant support:

The crown is attached to the screw-shaped titanium implant. Implant provides extremely strong support as it fuses with the bone, and there is zero risk of decay. The main risk here is loosening of the screw connection of the crown or inflammation that may occur if the area around the implant is not cleaned properly (peri-implantitis).

Experience

This is the main element that brings all these factors together and manages them.

An experienced dentist;

• Prepares the tooth in the correct amount and shape.
• Takes a perfect measurement (mostly with digital scanners).
• Correctly fabricates the temporary crown, protecting the gum tissue.
• Adjusts the fit with millimeter precision.
• Adheres the crown flawlessly in a dry and clean environment (ideally using a rubber dam).

Experienced dental technician:

Similarly, an experienced dental technician also processes the digital data or measurements they receive, creating the form, color, and surface texture that most closely resembles a natural tooth. The harmony between the dentist and technician team directly determines the quality of the result.

Oral care

Zirconia itself does not decay, but the natural tooth tissue around it can decay. Therefore, it is very important to keep the crown-tooth and crown-gum junction clean.

What should you do?

• Use a soft or medium-hard toothbrush.
• Brush the area where the crown meets the gum particularly well.
• Use dental floss. Place the floss against the tooth next to the crown, guide it downwards, and clean by tracing a ‘C’ shape. Do not be concerned about the floss going under the crown; if done correctly, it will not cause leakage but will clean that area.
• Interdental brushes are also an excellent tool for these areas.
• Have professional teeth cleaning done once or twice a year.

Dietary habits

Although zirconium is very strong, chewing ice, cracking nuts, or using your teeth as a tool (opening bottle caps, cutting thread) can cause irreversible damage to the coating. Excessively acidic beverages (cola, energy drinks, soda) and frequent snacking can also increase the acidity of the oral environment, raising the risk of decay in the tooth tissue around the crown edges.