These are all available in 3D Slicer. Panoramic image can be created by Curved Planar Reformat module in Dandbox extension.
There are many other very powerful features.
For example, the Curved Planar Reformat module provides invertible transform between the original CBCT and straightened space. This allows you to place implants in the panoramic image and get their position and orientation in the CBCT.
Slicer also provides fully automatic AI dental segmentations on CBCT, registration between intraoral scans and CBCT and much much more. I would recommend building any dental imaging application on 3D Slicer instead of just raw VTK. Slicer is built on VTK, just adds a lot of higher-level features, and it is all free, restriction-free, open- source - the same way as VTK.