How porcelain is made — a photo essay from the lab bench

A porcelain veneer is roughly half a millimetre thick at its thinnest point and weighs almost nothing in the hand. It is the visible, polished end of a chain that begins with a dentist's preparation and a photograph, passes through a ceramist's bench at a dental laboratory, and ends, if everything has gone well, invisibly bonded to a tooth in a patient's mouth. This essay is about the middle section of that chain — the part the patient never sees, the part a clinic rarely photographs, and the part that accounts for most of what separates a case that ages gracefully from one that looks wrong from the start.

The account below describes feldspathic layered porcelain built on a refractory die. Most premium anterior cases in Europe are still made this way. Pressed lithium-disilicate workflows — the IPS e.max Press family from Ivoclar is the reference point — compress the first two steps into a pressed ingot, but the stain-and-glaze stages after pressing follow a similar logic. Where a step differs for pressed or milled ceramics, the essay says so.

1. The prescription

The lab script is the bridge between the dentist's plan and the ceramist's bench. A good script includes the material requested, the target shade keyed to a physical shade tab, the design notes from the digital smile-design session, photographs of the patient in ambient light and under flash, a record of the bite, and the mock-up if one was fitted. A weaker script includes only the material and a shade.

This is the point at which the ceramist forms the first opinion about how the case will go. A detailed script with full-face photographs makes the rest of the work faster and better. A script that reads "B1 e.max, 2–10" is a case the ceramist will finish competently but rarely beautifully.

Plate — to be commissioned

2. The waxed model

The first physical artefact at the bench is a stone model of the prepared teeth, cast from the impression or printed from the intraoral scan. On top of this model, the ceramist builds the wax-up — a sculpture in wax of the proposed teeth, to the exact shape the finished porcelain will take.

The wax-up is where most of the aesthetic decisions already live. Width-to-length ratios, proportional relationships between central, lateral, and canine, the slope of the incisal edge, the depth of the gumline scallop — all of this is resolved in wax before any ceramic is touched. A good ceramist will photograph the wax-up at eye level and from below, and will send images back to the dentist for sign-off before proceeding. Labs that skip this step compress a week of aesthetic iteration into a single firing, and the compromise is usually visible in the finished case.

Plate — to be commissioned

3. The refractory die

To build a feldspathic veneer that can be fired without collapsing, the ceramist needs a heat-resistant support that the porcelain can be laid up on directly and survive the kiln. That support is the refractory die — a duplicate of the prepared tooth, cast from a heat-stable investment material, that goes into the furnace with the porcelain on it and comes out intact.

The refractory die is a specific, labour-intensive step that pressed and milled workflows eliminate. It is one of the reasons hand-layered feldspathic cases cost more to produce; it is also one of the reasons they look the way they look. The ceramist is working directly on a surface the same shape as the patient's tooth, at the same scale, under the same loupe.

Plate — to be commissioned

4. Powder and liquid — the build-up

Feldspathic porcelain arrives at the bench as a set of fine powders — dentine, enamel, incisal, effect shades, translucents — mixed on a glass slab with a modelling liquid to a consistency between toothpaste and clay. Using fine sable brushes, the ceramist applies the powders in sequence: an opaque core to mask the underlying preparation shade, a dentine body, an enamel layer, an incisal translucent at the biting edge, effect shades for characterisation. The build-up is done wet, with the ceramist constantly blotting the brush against absorbent paper to condense the powder.

The build-up is roughly 30% oversized at this stage, because the powder contracts substantially in the first firing. This is the step at which experience shows most visibly in the finished case. Younger ceramists tend to layer defensively and uniformly; senior ceramists modulate the layering case-by-case, reading the reference photograph and the wax-up on the bench.

Manufacturer powder systems vary. The IPS Style Ceram layering ceramic, the GC Initial family, and the Shofu Vintage range each have their own handling characteristics. A ceramist will usually work in one family for decades — switching systems is closer to learning a new instrument than to changing a tool.

Plate — to be commissioned

5. The first firing

The built-up porcelain goes into a programmable dental kiln and is fired under vacuum, typically somewhere between 800 and 930 degrees Celsius depending on the material. The temperature curve — how fast the kiln rises, how long it holds, how the vacuum is released — is set to the manufacturer's schedule for that powder. A ceramist running a modern kiln has the schedule stored in memory; a lab without good kiln protocols is a lab with inconsistent optical results.

What comes out of the first firing is about 20% smaller than what went in, fully dense, and, in a good case, already recognisable as the tooth it will become. What it lacks is fine surface texture and the final edge. Most cases are fired at least twice for that reason.

Plate — to be commissioned

6. The second firing (and sometimes a third)

After the first firing, the ceramist adjusts the shape and adds a correction layer — small additions of porcelain where the contraction has pulled the margin short, or where the incisal translucent needs to be deeper. Internal effect stains are placed between the layers in this second build-up: a faint halo, a subtle white spot in the enamel, a shadow at the gum line. The tooth goes back into the kiln.

Some cases require a third firing for a further characterisation layer. Every extra firing is a small biological stress on the porcelain and is planned, not accidental. Labs that fire five or six times to force the shape are labs that have not committed to the case on the bench.

7. Characterisation

Characterisation is the stage that separates a competent veneer from a persuasive one. The ceramist paints fine internal stains — browns, ochres, soft greys, occasional whites — into the porcelain to reproduce the small irregularities a natural tooth carries. A central incisor with no characterisation reads as plastic at three feet. A central incisor with a faint horizontal enamel band and a subtle incisal halo reads as a tooth.

There is a temptation, at this stage, to characterise heavily — because heavy characterisation photographs well under macro light. On the patient's face, heavy characterisation reads as theatrical. The discipline is restraint.

Plate — to be commissioned

8. Glazing

The final firing is the glaze — a thin, glossy outer layer that seals the porcelain and gives it the light-reflecting quality of enamel. The glaze is tuned to the finish the case requires: younger patients usually carry a higher gloss, older patients a softer matte. This is also where the ceramist decides whether the final texture will be smooth or carry subtle surface waviness — the so-called perikymata, the fine horizontal striations visible on young natural enamel.

The glazed veneer goes on a carding board under a bench lamp. If the ceramist holds it up against a white background, tilts it, and sees the internal colour shift as the light changes, the optics are working. If the veneer looks identical from every angle, it is too opaque, and it will read as opaque on the patient.

9. Delivery

The finished case is packed, numbered, and sent back to the dentist for the try-in appointment. In a lab where the ceramist sees the patient, the ceramist often attends the try-in — to watch the veneers on the face in the patient's own lighting, adjust internal shade if the light is warmer than the bench lamp, refine the incisal edge against the lip line. This is the last chance to correct. Once the case is cemented, further adjustment means removing material from the finished porcelain with a fine diamond, which never recovers the original optics.

The whole sequence, from impression to delivery, takes two to three weeks at a serious lab for a premium anterior case. It can be compressed to five days. It cannot honestly be compressed further.

Why this matters to a patient

A patient choosing between clinics is, whether they know it or not, also choosing between lab bench cultures. A clinic that works with a ceramist who layers feldspathic on a refractory die and fires twice to characterise is buying a different kind of case from a clinic that sends a scan to an offsite milling centre and receives monolithic e.max three days later. Both workflows have a place. A careful patient simply asks which one is being purchased in their case, and why.

Further reading

The biology on the clinic side of the workflow is covered in minimal-prep versus over-prepped veneers. The visual signatures a well-made veneer leaves on the finished smile are the subject of natural versus overdone veneers. For the broader framework a patient can use when evaluating clinics, see the decision framework.

References and spec sheets

• Ivoclar Vivadent — IPS e.max product family: pressed and CAD lithium-disilicate materials, including technical handling parameters.
• Ivoclar Vivadent — IPS Style Ceram: layering ceramic system referenced for feldspathic build-up.
• GC Europe — GC Initial: an alternative layering porcelain family, widely used in European labs.
• Shofu — Vintage / Ceramage: indirect and polymer-ceramic systems used in some hybrid cases.

By the Editorial team. Published 18 April 2026. Last reviewed 18 April 2026. Images indicated above are placeholder plates; commissioned photography is pending.