Metal-free prostheses: full ceramic and zirconia

For decades most crowns and bridges consisted of two layers: a load-bearing framework of metal and a ceramic veneer over it. Metal-free means that this framework too is of ceramic – usually of zirconium oxide, and for individual front teeth also of pressed ceramic.

The three reasons people want it

• No dark margin. If the gum recedes over the years, the edge of the framework of a metal-ceramic crown becomes visible as a grey seam. With a full ceramic crown there is no such seam.
• Light instead of a block. Metal lets no light through. Full ceramic does – which is why it looks livelier at the front, especially at the incisal edge.
• No metals in the mouth. Real allergies to dental alloys are rare; the wish is widespread all the same. Anyone who already reacts to nickel or palladium has a medical reason.

Where the limits are

Zirconium oxide is very hard and today also carries multi-unit bridges. Even so: the longer the span and the stronger the chewing force, the sooner a metal framework becomes the safer choice again. Space plays a role too – in some places full ceramic crowns need a little more substance than a thin metal cap.

With heavy grinding the problem is not the framework but the veneer over it: it can chip off. Some laboratories therefore deliberately leave the zirconia unveneered where nobody sees it.

What health insurance pays

The fixed allowance follows the findings, not the material. It stays the same whether you choose the standard care or a full ceramic solution – you carry the difference. In the visible anterior region a ceramic veneer is part of the standard care; in the posterior region it is not.

Which material is good for what is compared by the page Crowns of ceramic, zirconia or metal. How that affects the bill is shown by the treatment and cost plan.