I have not heard of anyone with a prosthetic tongue, but have talked with many patients that have had a muscle graft from another part of the body to the tongue after their glossectomy. The success of this path of reconstruction is heavily driven by how much of the base of the tongue is left. The graft is viable, living tissue, but without the nerves that allow a patient to control it to any great extent. If a significant portion of the original musculature of the tongue's base is retained, the patient is able to lift the anterior/front part of it, assisting in some speech sounds, but not offering much help in eating/swallowing. One of the tongues main functions of course, is to move a bolus of food to the back of the mouth for swallowing, and one that is mainly being controlled only from he posterior portion doesn't perform this task very well. Much of this is also dependant on physical therapy sessions to learn to manage the grafted tongue properly. Congratulations on your 2-year survival, and what is clearly a good attitude.