All-on-X scanning: when do you need photogrammetry and coded scan bodies?

In short: photogrammetry (IPG) and coded scan bodies are needed when the position of several implants across an entire edentulous arch has to be captured digitally – especially in All-on-X cases. With conventional intraoral scanning, image-stitching errors accumulate over a long edentulous arch, whereas photogrammetry determines the relative position of the implants from coded points. For single implants and short bridges, a conventional intraoral scanner with scan bodies is sufficient.

Why full-arch implant scanning is challenging

An intraoral scanner builds a 3D model by stitching together thousands of small frames. In a dentate arch, distinct tooth surfaces help to align the frames. In an edentulous jaw, such landmarks are lacking:

• the mucosa is smooth, mobile and shiny, making it harder for the software to match frames;
• the distances between implants are large, and an error accumulated at one end of the arch carries over to the other;
• standard scan bodies look identical, making it harder for the software to tell which is which;
• immediately after surgery, blood, saliva and unstable soft tissue get in the way.

For a full-arch restoration screwed onto several implants, an inaccurate relative implant position can result in an inaccurate fit of the restoration. That is why full-arch cases call for methods that capture implant positions independently of frame stitching.

Three methods: IOS, extraoral photogrammetry and IPG

SHINING 3D presents the Aoralscan Elite as the first device to combine intraoral scanning and photogrammetry in a single unit. The wireless Aoralscan Elite Wireless offers the same function. According to the manufacturer, IPG precision is 5 µm, and the coded scan bodies are compatible with the systems of more than 100 implant manufacturers. Important: the Aoralscan Elite Wireless NEO, Aoralscan 3 and Aoralscan Elf do not support photogrammetry.

When photogrammetry is really needed

• All-on-4, All-on-6 and other full-arch implant-supported prostheses – both immediate and definitive restorations.
• Several implants in a long edentulous segment, where there are no teeth to help stitch the frames.
• Immediate loading, when scanning has to be done right after surgery, with bleeding and unstable tissue.

When conventional IOS is usually sufficient: single implants and short implant-supported bridges with stable adjacent teeth.

It is important to understand that photogrammetry does not replace the entire scan: it accurately captures the relative position of the implants, but the soft tissue contour, the opposing jaw and the bite still have to be scanned in standard intraoral mode. The advantage of the Aoralscan Elite is that both data sets are acquired with the same device and in the same software, so there is no need to merge them manually from different systems.

Coded scan bodies: new and previous generation

A coded scan body has a unique geometric dot code, so the software recognizes each implant and accurately registers their positions. IMMT offers:

• New-generation coded scan bodies with a removable screw – the set includes 15, 20 and 25 mm scan bodies, tightened onto multi-unit abutments (MUA) at 10–15 N·cm with a torque wrench. Each has a unique serial number and a QR code for importing the library. The screw can be detached, cleaned and replaced separately.
• A previous-generation set with a one-piece design – for clinics expanding a system they already use.
• Spare screws (1 or 9 pcs) for the new-generation scan bodies – so that a procedure is never held up by a lost or worn screw.
• Scan Cap set (12 pcs) – makes data alignment easier immediately after implant placement, when the soft tissue is unstable or the surgical site is moist. Using at least 2–3 caps per case is recommended.

Before ordering, check compatibility with your implant system and MUA type – if in doubt, send us the name of your implant system.

A digital All-on-X workflow with IMMT solutions

1. Diagnostics and planning. Intraoral scanning, cone beam computed tomography (CBCT) data and 3D face scanning with the MetiSmile scanner. MetiSmile automatically aligns the facial data with the intraoral data, so the future dental arch can be planned according to facial proportions and the smile. MetiSmile MR additionally records the mandibular movement trajectory.
2. Surgical guide. The planned guide is printed in a transparent biocompatible resin: SHINING DENT SG01 for SHINING 3D AccuFab printers, HeyGears UltraPrint Surgical Guide UV for HeyGears printers.
3. Implant placement and MUA. The implants and multi-unit abutments are placed.
4. IPG scanning. Coded scan bodies are tightened onto the MUAs, and the Aoralscan Elite or Elite Wireless captures their position in photogrammetry mode; Scan Caps are used when the tissue is unstable.
5. Tissue and bite registration. The soft tissue, the opposing jaw and the bite are scanned, plus a face scan for esthetic assessment if needed.
6. Design and manufacturing. The lab receives the files in an open format (STL, OBJ, PLY) and designs a temporary or try-in prosthesis, which can be printed, e.g. in HeyGears On-X Teeth Try-in UV resin.
7. Fitting and verification. The clinician assesses the fit of the prosthesis and the occlusion according to their own clinical protocol.

The most common mistakes in full-arch scanning

• Insufficiently tightened or incorrect scan bodies. Follow the tightening torque specified by the manufacturer and use only scan bodies compatible with your implant system and MUA.
• Worn screws. A damaged thread can lead to an inaccurate scan body position – it is worth keeping spare screws on hand.
• Library not imported. The software must recognize the specific coded scan bodies by their serial number or QR code.
• Scanning an uncleaned or bleeding site. In immediate cases, Scan Caps are helpful, and the scanning area must be dried beforehand.
• Unclear communication with the lab. Agree in advance which files (IPG data, soft tissue, bite, face scan) the lab needs.

Checklist before your first IPG case

• The scanner supports IPG (Aoralscan Elite or Elite Wireless) and the software is up to date.
• You have compatible coded scan bodies, spare screws and a torque wrench.
• The coded scan body library has been imported into the software (QR code / serial number).
• Scan Caps are ready for immediate cases.
• You have agreed with the lab which files you will send and in what order.
• The team is trained – it is worth carrying out the first case with the supplier's support.

Get advice on your workflow

You will find scanners in the intraoral scanners category, coded scan bodies and caps in scanner accessories, and face scanners in the face scanners category. Contact IMMT – we will demonstrate Aoralscan Elite photogrammetry, help you choose coded scan bodies for your implant system and train your team.