Fair enough. After photon radiation to the throat for my SSC, within a very few years I began to have tooth issues on that side lower teeth. One tooth split which I had repaired yet ended up with a root canal. Then another root canal. Then infections in my gum in that same area. Eventually I required an extraction however the x-ray showed mandible structure to be roughly 50% of what it should be. No dental surgeon in my area wished to touch this procedure lest they break my jaw. Eventually I consulted Mayo Clinic who finally had a plan as they were well versed in this scenario.
Look for infections, pain while eating on that side, multiple tooth issues. Dental x-rays and specifically Panoramic x-rays will show deterioration of the mandible.