Mouth guard and lip biting

[Carriedoesntlivehereanymore]

My DS16 has recently got a mouth guard from the dentist to stop him grinding his teeth at night, but instead he's biting his bottom lip when he's asleep, resulting in cracks and bleeding in the morning. Obviously, he needs to wear the guard for the grinding, but he hasn't used it for a few days because of this new problem. Do we just persevere or does anyone have any tips?

Mouth taping?

I grind awfully, even with the mouth guard so my jaw was painful too. Mouth taping means I now rarely grind. Your DS wouldn’t be able to bit his lips if taped.

If he's wearing the mouth guard on the lower jaw, ask the dentist about trying one on the upper?

Thank you, I will look into mouth taping.

The guard is on his upper jaw.