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Zirconia: more than just good looks

In the field of dentistry, the list of available restorative materials are continuing to grow exponentially. The rate at which the names are added, is radical. The basic inspirations for the quest of new materials, are better aesthetics, better strength and longevity. The search is mainly done through research. Though most of materials are already part of our day to day usage. But still it is a wok in progress.

Among these restorative material is Zirconia. Though this has been on the market for some time, but its popularity is increasing for dental restorations.

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

It is now an established fact that aesthetics are now a primary focus for patients and dental practitioners. The recent trend has shifted towards natural looks. What were once considered as passable, are now considered as aesthetic failures. The reason behind is that they do not look natural. Even though many of the materials have the ability to perform function correctly and achieve appropriate longevity. But the criteria to become favorite among dental practitioners, is definitely good looks.

Of course, this approach is subjective. Dental aesthetics have more leverage in the anterior region where teeth are more prone to expose for display. In the posterior region, aesthetics don’t generally matter. The strength of the restorative material depends more. However, some patients will demand better aesthetics in posterior regions as well. So it’s important to establish the expectations of the patients and live up to them.

In accordance to above situation, zirconia obviously has an upper hand. Unlike other metallic or porcelain-fused-to-metal (PFM) crowns, zirconia can offer wonderfully natural looking aesthetics. Due to its atomic make up, the material echoes the appearance of natural teeth. This prevails in a number of ways, even in challenging conditions, such as changing lights. Furthermore, its naturally white hue means with careful shading it can become virtually indistinguishable from natural teeth.

Zirconia can become an ideal choice for high pressure aesthetic areas. However, it is important to remember not all zirconia is equal. Undoubtedly Zirconia, as a material, 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. This can put a negative consequence on their price range. As a dental practitioner, it’s worth exploring to see the expectations of patients. This may include level of aesthetics and adjustment of zirconia and to balance the outcome with cost.

Previously, most of the aesthetic restorations used had some downfalls. They didn’t have the functional capacity to work under stress. The earlier ceramic materials, simply couldn’t provide comparable strength as compared to natural teeth. Most of these options, have a higher fracture rate with occlusal forces. Metals though have comparably better strength when faced with such challenge. It is due to this reason that the focus was shifted to combine the aesthetics of ceramic with the strength of metal. Hench, PFM crowns were first invented. However, these crowns are also suspected to fracture and can chip its ceramic layer. Though it is stronger than most fully ceramic alternative restorations.

Zirconia can buck this trend in innumerable ways. The mechanical strength of the material can be up to three times stronger than other ceramic materials. This is due to the crystalline formation of this ceramic. Furthermore, zirconia has been proven to offer good long-term wear. It does not degrade substantially over time. This makes it 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. The difference altogether is very small but still significant. Zirconia is able to fracture under pressure. This still makes all-metal crowns, a better choice in posterior sites where aesthetics don’t matter much.

Researchers have recently proven that zirconia crowns can have 99.2% success rate in posteriors over a long period of time. Therefore, they are still a viable choice for crown placement in these sites.

Evidently, zirconia can easily be considered the gold standard for restorations in a wide array of cases. The use of zirconia for patients depends on the eagerness of patients. As 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. 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 patients.

Dr Muattar Hanif

The author is Editor at Dental News Pakistan and can be reached at newsdesk@medicalnewsgroup.com.pk