Why "how many days?" has no single answer
When a clinic asks how long a crown takes, the honest answer is "it depends on the case and on how quickly the questions get answered." A single monolithic zirconia crown from a clean scan can move through a lab quickly. A layered anterior case with a missing stump shade and a design waiting for approval over a long weekend can take far longer. Neither one is unusual.
Knowing the stages helps you see where your case is, which delays are normal, and which ones you can prevent.
The stages of a typical digital case
- Case intake. The lab receives the scan and prescription and checks that everything needed is there: upper and lower scans, a bite registration, readable margins, the material, the shade and the delivery address. If anything is missing, the case stops here until someone answers.
- Design (CAD). A technician designs the restoration in CAD software, setting margins, contacts, occlusion, thickness and emergence profile. Simple single units are usually fast. Bridges, implant cases and anterior esthetic cases take longer.
- Design approval. In workflows that include it, the clinic reviews the design before fabrication. This is often the most variable stage, because it depends on someone at the clinic finding time to open the design and respond.
- Milling or printing. The approved design is milled from a blank (zirconia, lithium disilicate, PMMA, metal) or printed (models, some temporaries and surgical guides).
- Sintering, crystallization or firing. Zirconia is milled oversized and sintered to full density, a furnace cycle that commonly takes several hours. Lithium disilicate goes through a crystallization firing. PFM and layered restorations need several porcelain bakes. Material choice therefore affects time even when the design is identical. See Zirconia vs. E.max vs. PFM for how materials differ.
- Finishing. Staining, glazing, polishing and, for layered work, hand-applied porcelain. Esthetic anterior cases spend the most time here.
- Quality check. Fit on the model or digital check, margins, contacts, occlusion, shade and surface finish. A case that fails QC goes back a step.
- Packaging. Protective packaging, plus any disinfection or sterilization the lab performs, and the paperwork.
- Shipping. Transit time from the lab to your door. For international labs, this also includes export, customs clearance and the last-mile carrier.
What slows cases down
Incomplete information
This is the most common delay and the easiest to prevent. Typical gaps:
- Material not specified, or specified vaguely ("ceramic crown")
- No shade, or no stump shade for a translucent material
- No opposing scan or bite registration
- Implant cases missing the implant system, platform size or scan body information
- Bridge or multi-unit cases where the tooth numbers on the order don't match the scan
Each question sent back to the clinic costs at least one round trip. If the lab is in a different time zone, one round trip can mean a full day.
Scan issues
- Margins hidden by tissue, blood or saliva
- Holes or stitching errors near the prep
- A bite scan that doesn't match the arches, or that was taken with the patient not fully closed
- Missing adjacent teeth, which the lab needs for contacts and emergence
A lab can sometimes work around a minor problem. A margin that cannot be read usually means a rescan, and a rescan means a new appointment.
Late design approval
When fabrication waits for clinic approval, the clock on the lab side effectively stops until you respond. A design sent on Friday afternoon and approved on Monday morning has lost the whole weekend, even though nobody did anything wrong.
Holidays and customs for international labs
An overseas lab follows its own country's holiday calendar, not only the US one. Long public holidays, such as Lunar New Year in several East Asian countries, can slow production and outbound shipping around those dates. Customs clearance is usually routine, but it can add days during peak periods or when paperwork needs correcting. US holidays in turn affect the domestic carrier at your end.
Rush orders
Rush service can shorten the queue, but it cannot shorten a sintering cycle or a customs inspection. It works best on cases that are already complete and need no back-and-forth. A rush order with missing information is still a delayed order.
How to plan seat appointments
- Count from approval, not from the scan. If your workflow has a design approval step, fabrication time starts when you approve.
- Use business days and check both calendars. Weekends and holidays in the lab's country and in yours both count.
- Build in a buffer. Book the seat appointment a few days after the expected delivery date, not on it. A short buffer absorbs a weather or carrier delay without forcing you to reschedule the patient.
- Plan temporaries for the realistic timeline. If a delay is possible, a well-fitting provisional matters more than an optimistic date.
- Separate high-stakes cases. For patients traveling, before a big event, or in a multi-stage treatment plan, schedule with extra margin. Send the case with no open questions.
Tips to keep cases moving
- Send a complete prescription the first time. Material, shade, stump shade, tooth numbers, implant details and any special requests.
- Check the scan before the patient leaves. Confirm the margins are visible, the bite is captured and the adjacent and opposing teeth are included.
- Make one person responsible for approvals. Assign who reviews designs and how quickly, and turn on notifications so approvals don't sit in an inbox.
- Answer lab questions the same day. A two-line reply can save a day of waiting.
- Send cases early in the week when you can, so design and approval don't straddle a weekend.
- Keep account details current. Shipping address, contact person and payment details, so nothing administrative holds a finished case.
How this works on HERi2go
HERi2go connects clinics, mostly in the US, with partner dental labs and aims to deliver within 7 days. Here is how the stages above map to the platform:
- Intake: you add HERi2go as a partner in your scanner cloud (iTero, Medit, 3Shape, Shining 3D, Dentsply DS Core or DEXIS) and send the case. The order form is generated automatically, and you review the order information.
- Design approval: the lab's CAD design is shared with you, and fabrication starts once it's approved, either by you or automatically if you've turned on auto-approval for that lab or placed a rush order (unless the lab requires your approval or your balance is short). You can approve from the web or from the HERi2go Clinic app on iOS and Android, which also shows case status. Payment uses prepaid points: the case is charged when the design is approved, and shipping is charged when the shipment is prepared. Keep enough balance so payment doesn't hold up an approval or a shipment.
- Questions: each case has a chat with the lab, with built-in translation. Replying promptly there keeps the case from stalling at intake or design.
- Before shipping: cases go through a quality check, protective packaging and plasma sterilization, then shipping from Korea to your clinic. Follow your own disinfection protocol before try-in as usual.
- Bundled shipping: your lab can combine cases headed to your clinic into one shipment, and each shipment carries a single shipping fee rather than one per case. The fee depends on your account tier, and rush cases ship on their own at the rush shipping rate.
- Design-only orders: when you order only the CAD design, there is no physical shipping stage. The lab delivers the design data instead.
Summary checklist
- Know the stages: intake, design, approval, milling, sintering or firing, finishing, QC, packaging, shipping.
- Most delays come from missing information, unreadable scans and slow approvals, and all three are in your control.
- Allow for the overseas lab's holidays and for customs on international cases.
- Count from design approval, use business days, and book the seat with a buffer.
- Assign one person to approvals and answer lab questions the same day.