Dental lab bookkeeping: cost the case, not just the invoice

The case is the unit of production — cost it like one

A dental lab does not sell hours, it sells finished appliances, so the case — a single crown, a three-unit bridge, a full denture, an implant abutment — is the thing that needs a real cost attached to it. That cost has two parts: the material that becomes the appliance (alloy, a zirconia or PMMA disk, porcelain, acrylic) and the technician time that turns it into a fitting piece — design, milling or hand-layering, finishing, polishing. We build a standard cost per case type from those two inputs, the same logic a small manufacturer applies to a bill of materials, so a single crown and a full-arch implant bridge are never averaged into one number that hides what each one actually costs to produce.

Design work in 3Shape or exocad, and the case-tracking system that follows a job from impression to shipment, both generate the data a standard cost needs: units produced, remakes, and time per stage. That data should land in QuickBooks Online as the ledger of record rather than live only inside the lab management software — a case cost is not a management number until it reconciles to what the lab actually paid for materials that month.

Alloy, zirconia and acrylic: inventory that moves with the market

Some of what a lab holds in inventory changes value on its own. Precious-metal alloys track the metals market, so a standard cost set when metal was cheaper understates every case that uses it until someone updates the number. Zirconia and PMMA disks, wax and porcelain are steadier but bought in bulk and consumed by the piece, which makes yield — how many usable units come off one disk after nesting and margin loss — part of the real cost, not just the invoice price. Scrap and filings from precious-metal work have value too: metal recovered and sold back to a refiner is a cost recovery, and it belongs against material cost or as other income, not buried in a miscellaneous account where nobody notices it happened.

Because appliances made on a dentist’s prescription are zero-rated rather than taxable, the input tax credits recovered on that alloy, zirconia and mill time matter even though no HST ever appears on the sale — see how input tax credits work for the mechanics we apply to every material purchase.

Dentist receivables: invoice it, age it, know who pays slowly

Labs bill the dentist, not the patient, which makes accounts receivable the account most worth watching closely. Some offices work from a monthly statement of everything shipped that period; others expect a per-case invoice matched to their own patient file; corporate and group-practice accounts often route payment through a head office on its own cycle, which tends to run slower than a solo practitioner who signs the cheque personally. We age receivables by dentist account rather than in total, because one slow-paying office disappears inside a blended number and becomes very visible once it is isolated. Remakes and warranty adjustments are credit notes against the original invoice, never a new expense line — the case was not truly re-sold, so the books should not treat it as one.

A close that ties the mill, the metal and the invoice together

Month-end for a lab reconciles three things: material purchases against the standard costs they support, technician time against cases actually shipped, and the receivable ledger against what dentists have actually paid. Whether a case counts as revenue when the impression arrives or when the finished appliance ships is worth deciding once and applying consistently — see cash versus accrual accounting for how we set that cutoff. Equipment payments on a mill, printer or sintering oven get split correctly too, principal against the loan and interest as an expense, because a leased scanner booked as a flat expense understates what the lab owns and overstates what it spent.

None of this needs to be elaborate for a lab your size; it needs to be consistent, which is what a fixed-fee monthly close is built to deliver. Material and equipment bought in US dollars carry their own bookkeeping rule, covered in our cross-border tax guide for dental labs; the monthly close itself runs through our bookkeeping services.