Has anyone published lab-side acceptance thresholds for intraoral scanner QC before full-arch work? I’m seeing RMS drift of 35–50 µm on a Medit i700 after firmware 1.3.2 using an ISO 12836 artifact, and I’d like guidance on tolerances and CBCT–STL registration (0.2 mm voxels) to keep implant positions clinically accurate.
guidance on tolerances and CBCT–STL registration (0.2 mm voxels) to keep implant We green‑light full‑arch only when ISO‑12836 RMS is ≤30 µm after a 10‑min warm‑up and fresh calibration, and for 0.2‑mm CBCT we merge with a 4‑fiducial bite fork, accepting ICP only if mean/95% TRE ≤0.25/0.5 mm; if you’re stuck at 35–50 µm on the i700 post‑1.3.2, try a slower anterior‑to‑posterior pass and exclude gingiva in ICP — what TRE are you getting on the merges?
Short answer from my side: I’m seeing the same pattern — one concrete thing that helped was writing down the exact handoff and timebox it to 15–20 min. Does that match what you’re running into?
Quick tip: when my i700 on 1.3.2 shows “35–50 µm” on the ISO 12836 bar, I add a thin suck‑down stent with 4 gutta‑percha fiducials, scan it with the IOS and include it in the CBCT; landmark-first on the fiducials and then a constrained surface refine only on scanbody flats keeps merges at “0.2 mm voxels” tight for full‑arch implants. If the stent’s a no‑go, a tiny dab of radiopaque flowable on canines works too — could you try a fiducial stent on your next case?