Laboratory Management, Quality Assurance and Digital Workflows
What is examined
Running a compliant, consistent laboratory: prescription control, traceability, quality systems, equipment calibration and the digital chain from scan to seated restoration.
Prescriptions and traceability
- A valid prescription identifies the patient, the dentist, the teeth involved, material and shade, design requested, and the date and signature. Keep it with the job record.
- Trace each prosthesis to its materials (batch or lot), the technician, the date and the equipment used, so a recall can be managed.
- Devices must meet New Zealand medical device obligations, and any claim you make about a product must be substantiable.
Quality assurance
- Written SOPs for each process, staff training records and competency sign-off.
- Calibrate and service equipment: surveyor, articulator, porcelain furnace, autoclave, mill and printer.
- Internal audits with corrective and preventive actions, plus a complaints and rework log. Trend the rework - recurring margin errors are a process fault, not a person fault.
Digital workflows
- Scan, STL, CAD design, nesting and milling or printing, then post-processing. Zirconia sinters at roughly 1450–1550 °C and shrinks about 20–25%, which must be compensated in the design; printed resin needs washing and post-curing.
- Verify scan quality, margin capture and occlusion before designing - digital errors stay invisible until the crown fails to seat.
- Protect patient data: encrypted transfer, access control, backups and consent for cloud storage.
Worked example
A zirconia bridge returns from the furnace with distorted margins. The unit had been resting against another in the sintering tray, so shrinkage was uneven. The QA fix is a documented sintering load protocol with a maximum unit count and recorded ramp and hold.
Traps
- Accepting a verbal or incomplete prescription.
- Recording no lot numbers, so a material recall cannot be actioned.
- Backing up only to a single unencrypted laptop.