Zirconia Restorations: Setting Expectations [Part II]
In my last article I provided some background information on zirconia full-contour restorations. This week I’ll discuss indications and contraindications for zirconia crowns.
Zirconia restorations are a great choice when you need something as strong as metal, yet are looking for a more esthetic result. Manufacturers have significantly improved the esthetics of the material over the last several years, allowing for a more natural looking result.
The major advantage of using zirconia over other materials besides its strength is that it allows you to make more conservative tooth reductions when compared to other ceramics. The space you need to create is more in line with what you need when prepping for a gold crown.
Indications for full-contour zirconia restorations include:
- Single posterior crowns
- Up to 4-unit posterior bridges
- Multiple tooth restorations
- As a replacement for gold crowns
- Masking of moderate to severe discoloration of underlying tooth structure
- As an alternative to a metal occlusal surface when a patient desires a metal- free restoration
- When the patient has parafunctional issues
- When you need to achieve maximum strength in an all-ceramic restoration
- When esthetic expectations are high and it is important that the restorations match surrounding natural dentition or other existing restorations
- If bonding is necessary to retain the restoration, bond strength is weaker and less predictable than other ceramics
When it comes to esthetics, the outcome typically can have the right color, but it could be higher in value because of its relative opacity compared to a natural tooth. This is why generally in anterior cases, full form zirconia is not the material of choice. However, the palatal aspect could be left in full zirconia with the labial aspect layered in order to achieve the appropriate translucency needed to blend with natural teeth or other ceramic restorations.