John Timothy Manal Greetings!
Azure Kinect DK provides a depth sensor that can be used to capture 3D depth data of the scene. This depth data can be used to segment the mouth or teeth area from the rest of the scene. You can then use this segmentation to apply a Teeth Whitening filter to the segmented area.
I would suggest you start with the below documentation and see if that helps.
Use Azure Kinect Sensor SDK image transformations
Do let us know if there any further queries.