Common problems that affect the roof of the mouth include leukolakia, dry mouth, thrush and taste changes such as a metallic taste in the mouth, explains WebMD. Infections, commonly caused by a virus or bacteria, can cause tenderness and swelling in all parts of the mouth, including the tongue.
Leukolakia causes thick, white and hard patches on the roof of the mouth that cannot be wiped clean, explains WebMD. Dry mouth, caused by dehydration, can affect the roof of the mouth and progress into gum disease and mouth infections.
Thrush is a common mouth problem that causes white patches to form that, when wiped away, appear raw and red, according to WebMD.