Implant scan body scanning tips for accurate impressions
Implant scan body scanning tips from the dental lab: preparation, capture, the errors that cause misfit, and the checks to run before sending the case.
An implant restoration can only be as accurate as the implant position in the scan. The scanner does not capture that position directly. The CAD software calculates it by matching a library model of the scan body to the scanned shape. If the scan body is incomplete, distorted or the wrong model, the design starts from a wrong position and careful work in CAD cannot correct it. These are the scan body scanning checks I ask clinics to follow, written from the side of the designer who receives the file.
Before scanning the scan body
Use the scan body that matches the implant brand and platform, or the multi-unit scan body for multi-unit cases. It has to match the library used in the design (see installing implant libraries in exocad).
Inspect it for scratches, deformation or worn surfaces, and follow the manufacturer’s rules on reuse. Tighten it as instructed so it is fully seated. A scan body that is not fully seated produces a scan that looks perfect with an implant position that is wrong, which makes it the hardest error to catch.
Clean and dry the area, because blood and saliva hide geometry. Turn the scanning feature toward a side the scanner reaches easily, usually buccal.
During the scan
When the soft tissue shape matters, scan the tissue around the healing abutment before placing the scan body, so the designer can see the emergence profile. Follow the scanning path recommended by the scanner manufacturer, since irregular paths increase stitching errors on long spans and full arches.
Capture the whole scan body, top and sides, together with the neighboring teeth or tissue. Keep the tongue and cheek away from the scan body surfaces and avoid reflections. Scan the antagonist and a correct bite as for any other case.
Full-arch implant scans
Long spans with several scan bodies and few stable references are the most difficult situation for any intraoral scanner. Accuracy depends on the scanner, the scan body design and the technique. Follow the scanner manufacturer’s protocol for full-arch implant scanning. When there is doubt about accuracy, agree on a verification step with the lab, such as a verification jig, before the definitive prosthesis is made.
Checks before sending an implant scan
- Every scan body is complete, with sharp edges and no holes.
- There are no doubled or smeared surfaces that suggest a stitching error.
- The bite is correct on both sides.
- The order states implant system, platform, scan body and planned component.
- The emergence profile scan is attached, if one was taken.
If any of these fails, rescan while the patient is still in the chair. It takes a few minutes, while the same problem found in the lab costs the patient another appointment.
What the lab does with the scan
The designer loads the library, aligns the scan body model to the scanned one and checks the fit visually and numerically. A good alignment is tight all around the scan body. A poor one shows deviations, and the designer should report it instead of designing on it.
From there the design follows the planned component: a Ti-base hybrid, a custom abutment or a multi-unit bridge (see implant abutment types). For everything else the lab needs from a scan, see the intraoral scan checklist.
Frequently asked questions
Why must the scan body be completely captured?
The CAD software aligns a library model of the scan body to the scan. Missing or distorted surfaces make that alignment uncertain, and the implant position in the design moves with it.
Can a scan body be reused?
Follow the manufacturer's instructions. Worn, scratched or deformed scan bodies change the geometry the software matches, so damaged ones must be replaced.
Should I scan the healing abutment area first?
A common approach is to capture the soft tissue and contacts with the healing abutment in place, then scan the scan body. Follow the workflow of your scanner software.
What should the lab receive with an implant scan?
Implant system and platform, the planned component (Ti-base, custom abutment or multi-unit), the scan body model, antagonist and bite scans, and the emergence profile scan when one was taken.