You wake up with a sore jaw and a headache that sits right behind your temples. Your dentist mentions “wear patterns” on your molars. You are grinding your teeth at night. The dentist recommends a custom mouth guard for $400, and you wonder if there is a cheaper way that does not involve sleeping with a piece of plastic in your mouth.

There is. Mouth guards protect your teeth, which matters, but they do not stop the grinding itself. Here is what addresses the root cause.

Progressive muscle relaxation before bed

Lie on your back in bed. Clench every muscle in your face as tight as you can — jaw, eyes, forehead — hold for five seconds, then release completely. Do the same with your shoulders, then your hands, then your legs. Work from head to toe. This teaches your body what deliberate relaxation feels like, and many people find their jaw stays looser through the night afterward.

Daytime awareness is the real fix

Most nighttime grinders also clench during the day — at their desk, in traffic, while concentrating. Set a phone alarm for every hour. When it goes off, check: are your teeth touching? If yes, separate them. Your teeth should only touch when you are chewing. After a few weeks of daytime practice, the habit often carries into sleep.

The warm compress trick

Before bed, hold a warm, damp washcloth against your jaw joint (right in front of your ear) for five minutes on each side. This relaxes the masseter muscle, which is the big jaw muscle that does the grinding. A relaxed muscle is less likely to fire involuntarily during sleep.

When to get the mouth guard anyway

If you have been grinding for years and your teeth are visibly worn, get the mouth guard. The relaxation techniques can reduce or stop the grinding over time, but they do not undo the damage already done. Think of the guard as buying time while you work on the underlying habit.