Digital facebow in exocad: aligning the scans to the articulator

An intraoral scan gives the lab the teeth and the bite, but not where the upper jaw sits in relation to the patient’s skull. The facebow records that position, and in a digital workflow it has to reach exocad as data, without a mounted plaster model. This post is for labs and clinicians who want to use a digital facebow in exocad, and it covers the ways the position gets into the software and the checks before the design starts.

What the facebow adds

The virtual articulator moves the models around a hinge axis. If the models sit in the wrong place relative to that axis, the movements are wrong too: a cusp that looks free in laterotrusion can still interfere in the mouth. For a single posterior crown the effect is small. For anterior guidance, full-arch work, splints and changes of vertical dimension, the position matters.

The virtual articulator guide explains the module and when dynamic occlusion is worth it. This post is about the step before: getting the models into the right place.

Four ways the position reaches exocad

exocad documents several ways to place the models in the Virtual Articulator. Which one you use depends on what the clinic recorded.

Transfer from the scanner

When plaster models are mounted in a physical articulator, some lab scanners transfer their position directly into the 3D space. The models then open in exocad already placed, with nothing to align by hand. This depends on a direct integration between the scanner and the articulator type, so the scanner provider has to confirm it.

Digital facebow data

In the Virtual Articulator there is a function called Load digital face bow data/articulator settings. It imports the model position and the articulator parameters from a file produced by a digital facebow or a measuring system. This is the cleanest route when the clinic has such a system, because the position and the values come from the patient.

Facebow registration digitized with the scanner

Many clinics still take a conventional facebow registration. Systems exist that digitize it with the intraoral scanner: the fork with its bite registration is scanned together with a reference part of known geometry, and a library in exocad uses that reference to place the upper arch. RotoClick is one example, built around a common facebow. The lab receives files only, and nothing has to be shipped.

Alignment without facebow data

When nothing was recorded, the models are placed in the articulator with Rearticulate models virtually. exocad offers manual correction, automatic alignment with three points (incisal point and one point on each molar), and alignment to a 2D patient photo loaded through Smile Creator. These methods rely on average anatomy. They are fine for many restorations and too approximate for cases built around guidance.

Checks before the design

Whatever the route, check the result before designing anything.

1. Look at the occlusal plane from the front and the side. A plane tilted in an unnatural way usually means a wrong point or a wrong reference variant.
2. Check the bite. The intercuspation must match the scanned bite registration, with no penetration of the arches.
3. Note the articulator type and the parameters in the case. A movement recording or a set of values belongs to one articulator geometry.
4. Run a short movement before the design. Strange paths at this stage are much cheaper to fix than after the anatomy is done.

What the clinic should send

For the lab to use a digital facebow, the clinic needs to send the intraoral scans, the bite, and the facebow data in the format the lab’s system expects, or the scans of the fork and reference part. A note with the facebow type, any reference variant used and the articulator values saves a phone call. The intraoral scan checklist covers the scan itself.

Teams that want to set up this workflow on their own system can learn it on their own cases in exocad training, from model placement to the movement checks on the finished design.

Frequently asked questions

Why does the facebow matter in a digital workflow?

An intraoral scan records the teeth and the bite, but not where the upper jaw sits relative to the hinge axis. Without that position the virtual articulator moves the models on average values, which can put interferences in the wrong place on larger cases.

Can exocad import facebow data?

Yes. In the Virtual Articulator, the function Load digital face bow data/articulator settings imports the model position and the articulator parameters from a file. Which systems produce a compatible file depends on the manufacturer.

What if no facebow was taken?

The models can be placed in the articulator manually, with three points (incisal point and one point on each molar), or aligned to a patient photo from Smile Creator. These methods use average anatomy, so they suit cases where the exact hinge axis matters less.

Which exocad module is needed?

The Virtual Articulator module. Recorded jaw movements need the Jaw Motion Import module on top of it.