You are very lucky to get treated by an excellent surgeon there. All the management and treatment plans had been done appropriately. Now the PET scan is planned to know whether there is any residual disease is there or not. It would have been better if a similar PET scan was taken after surgery and before starting the chemotherapy
so that we can compare it with the present scan. Any how it doesnot matter now. The toothache might be related to some pre-existing gingivitis
which might have flared becuse of the chemotherapy. This can be managed appropriately. Wish your mom a happy and healthy life...
Dr. Mohammed Ibrahim