Teeth grinding

So Abby has started grinding her teeth the last couple weeks, what can I do about it?, nothing that I know of. But man it is the most awful sound! I am just hoping that she doesn't chip the 4 she has in the process. I am hoping that the others trying to come in decide to come soon, she has become super grumpy in the evenings. I wish she was like the typical kid who would chew on a normal teethng ring type thing. But nope she loves her toothbrush!