For a little over a year now I have: Numbness  to my chin, lower lip that is constant, like when you get a shot novocaine by the dentist. I have had no dental work in over two years and no problems with my mouth such as sores, hit or had any facial accidents. In 2000, I had Tonsil cancer and had one tonsil removed and had over two months of radiation & chemo. In 2007, 08 & 10, I worked as a Security Contractor in Iraq.
Hi. Numbness to the chin and lower lip, as in your case, is attributable to many causes including bone infection, bone tumor/ cancer, trauma. Since you have a history of being operated for Ca Tonsil, it would be advisable, in my opinion, to get an OPG X-ray done for your jaw as a primary screening. Screen yourself for diabetes as well. Diabetes also causes peripheral neuropathy in certain patients causing lack of sensation in certain nerves. I would advise you, as I do in case of all my patients, to not ignore this symptom and get yourself properly examined. Regards.