Zirconia: strong and beautiful

 As zirconia becomes a more affordable option, Neil Photay muses on its viability for restorations in NHS dentistry

In dentistry, the list of available restorative materials continues to grow exponentially.

Inspired by the quest for better aesthetics or better strength and longevity, new materials are continually being explored through research.

Many being worked into day-to-day usage.

Zirconia has been on the market for some time and is increasing in popularity for NHS restorations.

But what are the benefits of this material and is it always the best choice for restorations?

The aesthetic edge

It’s no understatement to say aesthetics in dentistry are now a primary focus for patients and practitioners.

What were once considered passable outcomes are considered aesthetic failures if they do not look natural.

This is even if they perform function correctly – and can achieve appropriate longevity.

Of course, this is subjective.

Aesthetics will inevitably matter more in the anterior region where teeth are more on show.

However, some patients will demand better aesthetics in posterior regions as well, so it’s important to establish the expectations of those you treat, and live up to them.

In light of this, zirconia has an obvious benefit.

Unlike metallic or porcelain-fused-to-metal (PFM) crowns, zirconia can offer wonderfully natural looking aesthetics, even in challenging conditions, such as changing light.

Due to its atomic make up, the material echoes the appearance of natural teeth in a number of ways.

Furthermore, its naturally white hue means with careful shading it can become virtually indistinguishable from natural teeth.

This makes it the ideal choice for high pressure aesthetic areas.

However, it is important to remember not all zirconia is equal.

Zirconia as a material undoubtedly provides better aesthetics than resins or metals.

There are however, different varieties of the material available on the market.

Some will be more lifelike than others.

As such, it’s worth exploring to see what level of aesthetics your patient is expecting and adjusting the zirconia you use accordingly to balance outcome with cost.

A functional fit

Traditionally, more aesthetic restorations had some functional downfalls.

Some of the earlier ceramic options simply couldn’t provide comparable strength to natural teeth.

Many of these options have a higher fracture rate than metals when faced with occlusal forces.

It is for this reason that PFM crowns were first invented.

They combine the aesthetics of ceramic with the strength of metal.

However, these crowns are also prone to fracture and chipping on the ceramic layer.

This is despite being stronger than most fully ceramic alternatives.

Zirconia bucks this trend in a number of ways.

Due to the crystalline formation of this ceramic, the mechanical strength of the material can be up to three times stronger than other ceramic materials.

Furthermore, zirconia has been proven to offer good long-term wear.

It also does not degrade substantially over time, meaning it is an appropriate choice for permanent restorations. 

Despite these benefits, however, the strength of zirconia restorations can still come up short when compared to all-metal crowns, albeit only slightly.

Though zirconia is very strong, it is still able to fracture under pressure and all-metal crowns may be a better choice in posterior sites where aesthetics matter less.

That being said, research has proven that zirconia crowns have a 99.2% success rate in posterior locations over a long-term (7.4-year) period.

They are therefore a viable choice for crown placement in these sites.

An option for every patient?

Evidently, zirconia can easily be considered the gold standard for restorations in a wide array of cases.

The use of zirconia for NHS patients is relatively new having traditionally been reserved for private patients.

It is a more expensive material to produce compared to metals or PFM.

However, as the boom in popularity has continued, the price of zirconia is decreasing.

Coupled with bulk purchase of the material, it is now viable for NHS patients.

Zirconia restorations have proven their benefits in terms of strength and aesthetics.

However, it is still important to evaluate each case and discuss different options with your patients.