When she thought about what they might have started, her teeth ground together.

His teeth ground together, and he remained silent for a long while.

That's the first I've heard of the teeth grinding theory, it makes the most sense to me.

Nothing came over the circuit but the sound of teeth grinding.

Her teeth were grinding as she stared down at him.

There are a number of steps you can take to prevent teeth grinding.

My teeth ground together, and I released him, stepping backward.

His teeth ground together audibly in the silence of the room.

He bit down until his teeth were grinding against bare bone.

I think the other sound was my teeth grinding.