Often times, after a stroke, people will get "phantom" sensations in their face or body. The medical terms often used to describe these sensations are "allodynia" and "dysesthesia". They are
due to an interruption of the normal sensory pathways to the brain. These sensations can sometimes improve significantly over time. However, if they do not, and remain troublesome to you, I would recommend trying a medication to relieve the problem. Gabapentin and amitriptyline are inexpensive and often very effective. Lyrica and Cymbalta are more expensive, but can also provide helpful relief. In some cases, I also recommend accupuncture, but I am not sure that the accupuncturist would be able to help for sensations coming from the inside of the mouth. He/she would likely be able to help the sensations on the chin and in your thumb.