This was my makeup for Halloween 2015.
I made a plaster cast of my face, filled it with foam created by mixing Gorilla Glue and water. I used a high heat hot glue gun and white hot glue to make the teeth on some glass, popped them off and trimmed them to shape. Used pink hot glue on the face to hold the teeth in place and to make sure they'd fit my face. Spirit gum held them on. Black sclera lenses on my eyes to make them black.
Bonus: the teeth on my eyes chewed when my real mouth did.