CAD/CAM fabrication of zirconia restorations turns traditional manual steps into a digital workflow: data → design → milling → sintering → finishing. The main stages are below; the steps from milling to try-in follow the HD PLUS instructions for use.
Stage 1: data and design
The laboratory receives the impression or intra-oral scan, the opposing model, the shade and the dentist’s requirements. The technician builds the shape, contacts, occlusion and margins in CAD software. At design time, enter the scaling factor printed on the label of the blank lot to be used, because zirconia shrinks during sintering.
Stage 2: milling and rough finishing
- Fix the blank in the dedicated clamping holder.
- Start milling.
- Separate the milled framework from the blank and rough-trim with a diamond disc.
- Blow the dust off with an air gun.
Stage 3: staining and sintering
- Stain the framework with colouring liquid and dry under an infrared lamp, following the liquid’s instructions.
- Place the framework in the furnace.
- Select the sintering programme and start sintering according to the instructions supplied with the blank.
- Remove the framework once the furnace has cooled to room temperature.
Note: do not use the sintering parameters of another material for HD PLUS blanks.
Stage 4: inspection and finishing
- Check fit and margins on the working model; grind and polish if necessary.
- Sandblast with 50 micron Al₂O₃ at 2–2.5 bar and clean with a brush and water. Do not clean with steam.
- The framework is ready for porcelain layering: select porcelain and glaze to finish (for two-layer restorations).
- The restoration is ready for the dentist’s try-in.
Points to control
- Input data: a clear finish line and sufficient clearance.
- Scaling factor: the right blank lot.
- Sintering programme: the right material, with the furnace calibrated regularly.
- Lot records: keep the LOT and REF of the blank for traceability.
Detailed workflow can differ by restoration type and equipment; always follow the instructions supplied with the product.