If it's too long,
Buy him food for grinding his teeth,
Just cut it gently with scissors,
If there is blood, stop it.
He may not be able to shut up and touch for days,
Eat some glucose and liquid food, and it will be fine in a few days.
If you have difficulty eating in the future, don't eat hard food.
Drink porridge, or soak the feed in hot water.
But it's best not to cut this length.