D2 · 18 min
Digital impression quality
D2
Holes, blood, alignment drift, and the retraction the scanner cannot invent.
Real scan defects
These are unedited intraoral scans. Red lines are open edges — holes, tears, and overlapping shells the scanner never closed. Orbit. If you cannot see the finish line, you do not design.
Red lines are open edges — every hole the scanner never closed.
The scanner missed enamel: tongue, saliva, or a skipped pass. If a hole sits on the finish line you cannot mark it. Rescan. Do not paint the hole shut in CAD.
Also stop the design for
- Holes over the finish line — you cannot mark fiction.
- Double shells from a lip, cheek, or a second unaligned pass.
- An incomplete split or torn isthmus.
- Blood or saliva stretched into triangles.
- A bite scan that does not seat against both arches.
Read this
If you cannot see the margin, you cannot mark it
Retract. Dry. Rescan. A CAD technician who ‘paints in’ a missing finish line is designing fiction. The mill will copy the fiction.
Defects
Holes (black islands in the mesh), stretched triangles over blood, double gingiva from a lip that moved, occlusal holes from a tongue, and a bite scan that does not seat against both arches. Any of these is a rescan, not a heroic smooth.