I have had a recurring problem with deep cracks in my tongue, and super-sensitivity to spicy and salty foods.  I have seen a dentist, a dental surgeon, the head of Baylor College School of Dentistry, my primary physician, and a gastroenterologist. etc. on and on.  No one has the faintest idea what it is.  It disappeared for six months when I was hospitalized with pneumonia and had antibiotics for about three months. It also affects the toothpaste I can use without burning.  I am 75 years old, have been in good health all my life.  Thank you.
Pl review with your doc. Is it something like a geographic tongue? Need to check that. That disease causes burning sensation to hot and spicy foods. The pattern of cracks changes. Usually associated with emotional stress. Needs no treatment as such.