The dentist removed the old PFM and sent us photos. The underlying picture:
- Cast nickel-chromium post, intact, no mobility
- Remaining tooth structure: a thin ferrule, about 1.5 mm of circumferential dentin coronal to the margin
- Core shade: dark gray with a brown undertone — darker than any tab in the standard VITA range, closer to what you'd expect from a long-standing metal post leaching color into the surrounding dentin
- Prep margin: supragingival on the labial, equigingival on the lingual
- No decay, no fracture lines, no mobility of the root
Space measurements from the digital scan:
- Labial clearance: 1.2 mm
- Incisal clearance: 0.8 mm
- Palatal clearance: 1.1 mm
The dentist noted that any additional reduction would compromise the ferrule. He wasn't willing to go deeper.
Adjacent teeth. Tooth #9 (the opposite central): natural, unrestored, A3 on the VITA Classical, mild cervical darkening, incisal translucency on the higher end. Teeth #7 and #10 (laterals): both natural, A2 at the body, slightly lighter at the incisal, no visible restorations.
Opposing arch. Lower anteriors natural and well-aligned, normal overbite, no edge-to-edge contact. No parafunctional wear patterns on the incisal edges of the lower teeth, which told us she wasn't a nighttime grinder.
Shade history. The patient had done a two-week at-home tray bleaching about four months before the case started. She stopped halfway through — she said the sensitivity got too much to continue. Her teeth settled at roughly A2 across the laterals, A3 at the other central. Her target for the new crown was A2, matching the laterals, with the understanding that #9 would stay slightly warmer.
What she said she wanted. She brought a photo of herself from a holiday six years ago, before the second PFM started showing metal, and said she wanted this tooth to look like it did in that photo — not whiter, not different in shape, just not noticeably "the crown." Her daughter was getting married in six months. She wanted to be able to smile in the photos without thinking about it.
That last part didn't change the technical approach, but it did change the margin for error. There wasn't much.
What the Dentist Asked For
The prescription was tight:
- Mask the dark core. Full stop. He didn't want gray showing through.
- Match #9. Specifically #9, not an abstract A2. He sent a cross-polarized photo of the two centrals and the laterals, all captured with a VITA tab in frame for calibration.
- Don't make it thicker. He'd prepped carefully to preserve the ferrule and he wasn't going to re-prep. What we had was what we got.
- Keep the incisal looking alive. His exact words: "I don't want it to look like a chalk tooth at the edge." He wanted some translucency where #9 had translucency.
He also told us, on a short call before we started milling, that he'd use an opaque resin cement — his standard was a dual-activation luting composite in A2 opaque. He said that upfront because he knew it mattered. Cement shade accounts for about 27.6% of the final color match on monolithic zirconia over discolored substrates, and he wasn't about to leave that variable floating.
What he didn't ask us to do: anything beyond the single tooth. No veneers on the adjacent teeth, no mock-up on #9, no attempt to level the shade across the arch. One tooth, one job.
What We Did
We milled from a layered 5Y-PSZ zirconia block. The reason wasn't strength — this is a single anterior, light occlusal load, no bruxism signs. The reason was the gradient. The block has a denser, more opaque cervical third and a translucent incisal third built into the same disc. We needed both in different parts of the crown, and getting them from a single block meant we didn't have to build up an opaque liner inside the restoration — which would have eaten into the cement space we didn't have.
The crown was nested in the block so the cervical margin sat in the opaque segment. That segment would end up directly over the gray part of the post and the darkest dentin around it. The incisal edge was nested in the translucent third. We ran the orientation check twice before cutting — if you position a multi-layer block incorrectly, the gradient works against you instead of with you.
Internal design:
- Full-contour, no cutback on the labial
- Wall thickness: 1.0 mm at the cervical, tapering to 0.9 mm at the incisal tip
- Internal cement gap: 60 microns at the occlusal/incisal, 40 microns at the margin
- No separate opaque liner — the block's cervical segment handled that
The 0.9 mm at the incisal was a deliberate call. The dentist's clearance was 0.8 mm there, which was already tight. We built the crown to 0.9 by borrowing 0.1 mm from where the opposing cuspid tip would have sat during protrusion, after checking the dynamic occlusion against the scan. That gave the translucent zone a bit more depth to show in without hitting the opposing teeth.
After sinter, the crown measured warmer than A2 under daylight-corrected lighting. The dark core was ghosting through more than the scan had predicted — not grossly, but enough to pull the body shade into the A3 range. We corrected with external characterization: a dilute A2 wash on the labial surface, with a small amount of BL2 bleach-shade tint blended into the mid-third to lift the value, then re-glazed and re-fired. One pass, no over-firing.
The margin ridge got a light stain pass to pick up a hint of warmth near the gumline — matched to the slight cervical darkening on #9 we'd seen in the dentist's photos. If we hadn't done that, the crown would have read "too clean" against a tooth with normal gingival chroma.
Return slip to the dentist carried one line we underlined: Use the A2 opaque cement as planned. A translucent cement will let the post ghost through. He'd already said he would. We said it anyway, in writing, so the chart had it.
Total production time from scan receipt to shipment: nine working days. Longer than our standard five-to-seven on a single anterior, but this case needed one design preview, one phone conversation, and the second firing after the first color check. Rushing any of those was how the crown would have come back for a remake.
Try-In: What the Patient and Dentist Said
The dentist seated it dry first — no cement, just finger pressure — and brought the patient to a mirror.
Her first reaction, quoting the dentist's follow-up email: "She just looked at it for about thirty seconds without saying anything. Then she said, 'that's the one.'"
She did have one question, and it was a good one. Under the operatory light, she could see a very faint cooler undertone at the incisal edge compared to #9. Not a visible gray — more like the restored tooth had a touch less warmth in the top millimeter. She asked the dentist whether that would be obvious to other people.
The dentist walked her over to the window and held the mirror in natural light. The undertone softened. He asked her to smile at conversational distance and look at her reflection from across the room. From there, both centrals read as the same tooth.
He explained — accurately — that layered zirconia with a dark core underneath can't match the full translucent depth of an unrestored tooth without more thickness than her prep could give. We'd told him that before milling. He told her. She said she understood, and she still wanted to go ahead.
Dentist's technical check after dry seating:
- Margin fit: fully seated, no rock, no detectable gap on explorer walk-around
- Proximal contacts: light floss resistance mesial and distal — matched his request
- Static occlusion: no premature contacts, equal shim-stock hold on #8 and the adjacent teeth
- Protrusive and lateral: no interference on #8, group function preserved
- Shade under daylight-correction: within one half-step of #9 on the VITA scale, slightly cooler at the incisal third as predicted
He wrote back the same day. The exact line: "Patient is happy, I'm happy, going to cement tomorrow with the A2 opaque as discussed."
The cementation visit was the next morning. He used the A2 opaque resin cement, isolated with rubber dam, polymerized through the labial surface, cleaned excess at the sulcus. Final seating was uneventful.
The Final Result
She came back for a one-week post-cementation check. No cold sensitivity, no biting discomfort, no issue chewing on the tooth. The gingival margin around the crown — which had carried that faint gray halo from the old PFM — had started to lose some of its darkness. The dentist thought that would continue over a few more weeks as the tissue adjusted to the new margin without the metal collar.
Shade-wise, the crown read as expected. Under operatory light the cooler incisal undertone was visible if you were looking for it. Under natural light, at the distance anyone would actually see her, it blended.
She came back a second time, three months later, for a cleaning. The dentist took another retracted photo and sent it to us for the file. Same reading as week one. The crown hadn't shifted color — which it shouldn't, because zirconia doesn't shift color — and the surrounding tissue had settled fully. No more gray halo at the gumline.
She was at her daughter's wedding four months after that. The dentist got a text with a photo of her smiling in the first dance. He forwarded it to us with one line: "Can't tell which one is #8."
That's the measure we were working toward. Not a flawless match under magnification — we weren't going to get that in 1.2 mm over a nickel-chromium post. A match that disappears in the context people actually see her in. On that bar, the case worked.
Why Dentists Send Us Cases Like This
A case this tight needs a lab that owns every step of the workflow. We're that kind of lab.
Everything happens under our roof. We've been running since 2012 out of our own facilities in Shenzhen and Huizhou. CAD design, model printing, CAM milling, zirconia processing, porcelain and glaze work, polishing, QC, packing — all in-house. Nothing gets farmed out to a third party. For a case where orientation inside the block, firing temperature, and surface stain all have to line up, that kind of control matters. If something looks off at QC, the technician who milled it is still in the building.
A team sized for the work. Around 460 technicians across the floor — about 100 in CAD, 70 in milling, 70 in ceramic and metal, 25 in QC, plus a 40-person case coordination team that handles the back-and-forth with the dentist's office. For anterior cases, the design and ceramic work goes to senior technicians who do them every day. Not whoever happens to be free.
Capacity for whitening zirconia crowns, in volume. Around 8,000 single zirconia crowns a month under normal load, up to 15,000 in peak season. One demanding anterior doesn't bump a routine case off the schedule, and a batch of twenty posterior crowns doesn't push your single central to the back of the queue.
Response time that fits your day. Technical questions get answered within an hour during our working window. If you're in a different time zone, worst case is roughly 12 hours — overnight for you, same business day for us.
Account manager assigned to you. Not a shared inbox. One person who knows your preferences, your previous cases, the shade targets you tend to run, and which materials you prefer. If a case needs a design preview or a pre-mill conversation like this one did, that's who sets it up.
Communication in English, on the systems you already use. Scan files through 3Shape, iTero, Medit, exocad — we take them in their native format. Written case notes, phone calls, video reviews for complex anteriors, all in English. We can also sign NDAs, quality agreements, or complete your supplier onboarding questionnaire if your practice requires it.
On record where it counts. Active registrations include FDA facility registration, MDR notification, MHRA listing, and an ISO 13485 quality system in operation. Clinics have audited our site over video; some have flown in to Shenzhen for a walk-through. Both are open to you.
Markets we already serve. More than 400 dentists, 100-plus clinics, and 50-plus laboratory partners across the US, Netherlands, Germany, France, Belgium, Austria, UK, Luxembourg, and Switzerland. The workflow for your case is the one we run every day.
How to Send Us a Case
A case like the one above started with a scan, a few photos, and a short note. Here's what we need from you to get moving, and how to send it.
For a digital case, send:
- Upper and lower arch scans, plus the bite scan
- A clear scan of the preparation itself — margin visible all the way around
- The target shade and the parent tooth it should match to (not just a VITA tab name — a photo of the tab held next to the tooth, under daylight, is far more useful)
- The stump shade or a photo of the prepped tooth before the scan, so we can judge how much the substrate will push through
- Any special notes: anti-rotation feature, cement space preference, incisal translucency expectation, or restrictions on reduction
For a physical case, send:
- The impression or model, well packed, with the opposing and bite record
- The same prescription and photo set as above
- Any shade tab the dentist used chairside, if available
Where to send it.
- Digital files: through your scanner's cloud portal, a shared drive link, or straight to your account manager's inbox
- Physical cases: ask us for a shipping label and we'll arrange pickup, or ship to our Shenzhen address with the tracking number sent across
Prescription basics we need on every case:
- Patient reference (an ID or code — a name is not needed and we'd rather you didn't include one)
- Tooth number
- Material and shade target
- Occlusion notes (clenching, bruxism, limited clearance)
- Preferred cement type if it's going to drive the design
First time working with us? A single test case is fine. We take trial orders. You send one unit, we deliver on the same workflow we'd use for a full batch, you decide whether the fit and the color are what you expected. No account to open before the first case. The paperwork catches up once you're happy.
Need it faster than our standard turnaround? Tell us at the point of submission. Rush is possible on most case types and doesn't carry a surcharge if the design is clean on arrival. If we flag something that needs a rescan or a conversation, that resets the clock — so the cleaner the submission, the shorter the clock.
Send your next whitening zirconia crowns case through, and we'll quote the design and the delivery window before any milling starts.