Teeth material bugged! Help please!

I am in the process of modelling a character in Blender 2.70a. I am almost finished with this character, but the teeth are glitched, as seen in this screenshot:

The teeth are not a texture, just a material applied to the teeth and gums. Here is the .blend file: Andy.blend (1.3 MB)

Thank you in advance to anyone who can help out!

What you see is called z-fighting and occurs when you have duplicated faces in the same location. Go to edit mode, select all and do “remove doubles”