This is one of the most frequent questions in consultation. And it is also one of the most poorly phrased.
Most patients arrive with the zirconia versus porcelain-fused-to-metal crown opposition. For them, that is the question. However, today’s clinical debate takes place elsewhere: between monolithic zirconia and lithium disilicate, two metal-free ceramics that cover almost all indications.
Here is how Dr. Zerguine approaches the choice at Dental Swiss Clinics in Montreux.
What patients misunderstand
When a patient talks to me about zirconia, they almost always contrast it with the metal crown covered in porcelain, the one they know, sometimes on their own tooth. Lithium disilicate is not in the conversation. Often, they have never heard of it.
It’s understandable. Zirconia has been widely marketed as the modern alternative to metal. But this simplified presentation has a side effect: it leads people to believe there are two options, when there are at least three, and zirconia is not always the best one.
The three materials to know
Porcelain-fused-to-metal (PFM)
A metal base covered with porcelain. Strong, proven, used for decades. Its flaw: a gray line that can appear at the gum line over time, and aesthetics limited by the presence of metal under the ceramic. Today, it is less and less indicated for visible teeth.
Lithium disilicate
A metal-free ceramic, heavily used for single crowns and veneers. Its main asset: a natural translucency, close to a living tooth, which gives excellent aesthetic results. Its requirement: it needs thickness. An occlusal reduction of about 1.0 mm is necessary to guarantee strength and aesthetics.
Monolithic zirconia
A much harder metal-free ceramic, capable of functioning in thin layers. Clinical studies document high survival rates with occlusal thicknesses of 0.5 to 1 mm. Its aesthetics have progressed significantly with new multilayer generations, but it remains slightly behind disilicate in terms of translucency.
The real decision criterion
In my practice, what determines the choice between disilicate and zirconia is not aesthetics as a first priority. It is the available vertical dimension.
If the prosthetic space between the prepared tooth and the opposing tooth is sufficient, I work with lithium disilicate. Translucency, integration, direct fabrication at the clinic in one visit with CEREC. It is the gold standard solution for the vast majority of posterior and anterior single crowns.
If space is limited, typically on an implant crown in the posterior zone when the prosthetic height is low, zirconia becomes the right choice. It allows me to create a thin crown without compromising strength, where disilicate would not hold up over time.
This is precisely what scientific literature confirms: monolithic zirconia maintains sufficient strength at thicknesses where other ceramics fracture.
When I place a zirconia crown
Very rarely on a natural tooth. In my practice, the main indication is the implant crown in the posterior sector, when the space between the implant and the opposing tooth is reduced. In this specific situation, zirconia is clinically the best option.
For other situations, lithium disilicate is the reference material at Dental Swiss Clinics, manufactured at the clinic in a single visit.
And porcelain-fused-to-metal?
It still has a place in certain specific situations, but it is rarely the first choice today. The dual requirement for metal-free aesthetics and high marginal precision driven by digital technology has shifted the center of gravity toward disilicate and zirconia.
What it means for the patient
Concretely, when a patient asks “will you use zirconia?”, the right answer is not yes or no. It is: it depends on the tooth, the available space, and the objective. My role is to explain the reasoning, not to propose a material because it sounds better.
A successful crown is not a zirconia or disilicate crown. It is a crown in the right material, in the right place, designed and placed by the same practitioner in a complete digital workflow.
Frequently Asked Questions
Is zirconia stronger than disilicate?
Mechanically, yes. But that is not enough to make it the best choice in all cases. Disilicate offers superior aesthetics and more natural integration, making it the reference material when sufficient thickness is available.
Can lithium disilicate break?
Like any ceramic, yes, but under specific load and thickness conditions. When the indication is correctly set and the thickness respected, its longevity is clinically documented over long periods.
Why not use zirconia everywhere, for safety?
Because its translucency remains slightly lower than disilicate, and its very high hardness can wear down the enamel of opposing teeth if the surface is not correctly polished. Using zirconia where disilicate is sufficient means missing out on optimal aesthetics.
Should porcelain-fused-to-metal be preferred for posterior teeth?
Not as a first choice. Disilicate and zirconia now offer strength compatible with posterior forces, without the aesthetic compromise of the gray line.
Can all crowns be done in one visit at Dental Swiss Clinics?
The vast majority of lithium disilicate crowns are manufactured and placed in a single visit with CEREC. Zirconia crowns on implants follow a slightly different workflow, explained during consultation.
To assess your situation, contact Dental Swiss Clinics in Montreux, Monday to Friday from 8 AM to 8 PM.