question: I used braces 8 years ago and I use retainers to sleep only. Last week I went to the dentist because I feel a snap when I close and open my mouth.The Dentist told me that I grind my teeth and he suggest me to use a night guard, and change one of the retainers. He told me that the snap will stop when I use the night guard. My question is should I use the night guard or continuing with the old retainers?cm