Zirconia and E.max crowns: which is used for what

Zirconia and E.max are frequently presented to patients as a straightforward choice between a “premium” option and a “standard” one. That framing does not reflect what the materials actually are. They are two different classes of dental ceramic, each with a distinct balance of strength and appearance, and the right choice depends on the tooth being restored — not on which one carries the higher price tag in a given clinic.

What dental zirconia is

Zirconia used in dentistry is a crystalline ceramic (zirconium dioxide) valued for its strength. It is not one uniform material: different generations and formulations of zirconia trade strength against translucency. Earlier, high-strength zirconia formulations are more opaque and better suited to substructures or posterior teeth where strength matters more than light transmission. Newer, more translucent zirconia formulations sacrifice some strength for an appearance closer to natural enamel, making them more suitable for visible front teeth. This means “zirconia crown” alone is not a complete description of what you are being offered — the generation and formulation matter, and a clinic or laboratory should be able to tell you which one is being used and why for a given tooth.

What E.max is

E.max (IPS e.max) is a branded product line built from lithium disilicate, a glass-ceramic material valued primarily for its translucency and ability to mimic the light-handling properties of natural tooth enamel. It is generally regarded as more aesthetic than earlier ceramic materials, particularly for visible restorations, though it is mechanically different from zirconia rather than simply “less strong” — the two materials fail differently under load, and a fair comparison depends on where in the mouth each is used.

What the evidence actually reports

A systematic review of the survival and complication rates of zirconia-ceramic and metal-ceramic implant-supported single crowns (Pjetursson, Valente, Strasding, et al., Clinical Oral Implants Research, 2018), which pooled 35 studies with at least three years of follow-up, found an estimated five-year survival rate of 98.3% for metal-ceramic crowns and 97.6% for zirconia crowns — broadly comparable, though the review also found that significantly more zirconia crowns failed specifically due to material fracture (2.1% versus 0.2% for metal-ceramic), while rates of ceramic chipping were similar between the two groups. The same review noted that no studies of newer monolithic zirconia crowns met its three-year follow-up inclusion criteria at the time, meaning this comparison largely reflects earlier zirconia generations rather than the most recent formulations in use today.

For lithium disilicate, a systematic review of tooth-supported single crowns and fixed partial dentures (Pieger, Salman & Bidra, The Journal of Prosthetic Dentistry, 2014), based on 12 clinical studies, reported a 2-year cumulative survival rate of 100% and a 5-year rate of 97.8% for single crowns, with survival for multi-unit fixed partial dentures notably lower (78.1% at five years) — the review's authors specifically noted that lithium disilicate single crowns had excellent short-term evidence, but that medium-term data was more limited, and that most failures in both restoration types occurred in posterior (back-of-mouth) teeth. A more recent overview of 28 systematic reviews covering roughly 35,000 lithium (di)silicate crowns (Laumbacher, Scholz, Knüttel & Rosentritt, Journal of Dentistry, 2025) concluded that these crowns show “excellent short- and medium-term survival rates (95–100%) in the range of metal-ceramic crowns,” while also flagging substantial methodological variation between the underlying reviews and a shortage of long-term (beyond five years) data.

Read together, both materials report survival rates in a similar, generally high range over the periods studied, in the context of metal-ceramic crowns as a long-established comparison point. Neither body of evidence supports a blanket claim that one material is simply superior to the other across all situations — the differences that show up relate to failure mode (material fracture versus chipping) and to which part of the mouth the crown sits in, not to one ceramic being uniformly stronger or more durable in every respect.

Front teeth and aesthetic demands

Where appearance under natural light and translucency matter most — typically the visible front teeth — lithium disilicate and the more translucent zirconia formulations are both commonly used, and the choice between them often comes down to the specific tooth's remaining structure and the technician's assessment of shade-matching against neighbouring teeth, rather than one material being categorically the aesthetic choice.

Posterior teeth and loading

Back teeth carry substantially higher biting forces than front teeth. High-strength zirconia formulations are frequently favoured here because of their fracture resistance under load, particularly in patients who grind their teeth (bruxism) or have a heavy bite. This is a functional consideration specific to the tooth's position and the forces it will bear, not a general statement that zirconia is “better” than lithium disilicate everywhere in the mouth.

What the long-term result actually depends on

The material named on your treatment plan is only one factor in how a crown performs over years. At least as important are: how much of your own natural tooth structure remains before the crown is placed (a heavily broken-down tooth behaves differently under any material than one with minimal preparation), the preparation technique used, the adhesive (bonding) protocol followed at cementation, the accuracy of fit between the crown and the tooth, the crown's thickness at its weakest points, how the crown has been adjusted to your bite, and the quality of the laboratory work and planning behind it. A well-fitted crown in a less fashionable material, seated on a tooth with adequate remaining structure, can outperform a premium-branded crown poorly fitted onto a heavily compromised tooth. Material name alone tells you very little about how a specific crown will perform in your mouth.

The question to ask

Rather than asking which material is “premium,” ask your treating clinician: why is this specific material being proposed for this specific tooth, given its position in my mouth, the forces it will carry, and how much of the natural tooth remains? A clinician who answers by reference to your tooth is giving you a clinical answer. A clinic that answers by reference to price tiers is giving you a sales answer.

It is reasonable to ask, too, whether a mock-up or trial restoration will be shown to you before the definitive crown is fabricated, particularly for visible front teeth where shade and translucency matter most to you personally, since a photograph of someone else's result in either material tells you little about how it will look against your own remaining teeth and gum tone.

What to do next

Before agreeing to a crown material, ask which generation or formulation of zirconia, or which lithium-disilicate product, is being proposed, and why for that specific tooth rather than as a blanket choice across your whole treatment plan. You can check whether a treating facility holds a current Ministry of Health authorisation through the dental register. Our related guides on dental treatment in Turkey and All-on-4 versus All-on-6 cover the wider planning questions that apply alongside material choice in larger cases.