When you are creating a new 3D actor's head by setting the facial details or morphing the facial features in the Front Face Fitting or Side Face Fitting steps, the eyeballs, teeth and tongue sometimes pop out of the skull especially when the profile of the actor is very exaggerated as shown below:
This issue often occurs during the Side Face Fitting step. When you encounter this problem, you need to recalibrate by following the steps below:
You can also rotate the teeth and tongue by dragging the Teeth and Tongue Rotate slider if needed.