Upper vs Lower Night Guard: Which One Is Right for You?

If you grind or clench your teeth at night, a custom night guard is the standard protection. But which arch should it go on, your upper teeth or your lower? Most people wear an upper guard, and most dentists fit them by default. That said, a lower guard is genuinely the better choice for some mouths. Here is how to decide.

The short answer

Either arch protects your teeth, because a guard only needs to sit between your upper and lower teeth to absorb grinding force. The choice comes down to comfort, your dental history, and a few practical factors. You only need one guard, not both.

When an upper night guard makes sense

Upper guards are the default for good reasons:

• The upper arch is larger and more stable, so the guard tends to stay put
• Upper guards interfere less with tongue movement for many people
• They generally work well for average bites without special considerations
• Dentists have the most fitting experience with them

If you have no strong preference and no special dental circumstances, an upper guard is a safe choice, and it is the configuration most Remi customers wear.

When a lower night guard is the better call

Lower guards win in several specific situations:

• Strong gag reflex. Lower guards trigger gagging far less because they sit away from the palate.
• Upper dental work. Veneers, bridges, or implants on top? Many dentists prefer to fit the guard on the opposite arch rather than over restorations.
• Mouth breathing and airway concerns. Some people find a lower guard less obstructive to airflow.
• Comfort preference. Some people simply tolerate a lower guard better and wear it more consistently. The best guard is the one you actually wear every night.

Does one protect better than the other?

No. Protection comes from the barrier itself, not the arch it sits on. What matters far more is fit and material. A custom guard made from your own impressions distributes force evenly; a loose boil-and-bite guard concentrates it. If you want the comparison in depth, see our guide to custom vs boil-and-bite guards.

Thickness and material matter more than arch

Whichever arch you choose, match the guard to your grinding severity:

• Soft: light grinding or clenching, maximum cushion
• Hybrid (soft interior, hard exterior): moderate grinding, the most popular option
• Hard: severe grinding, maximum durability

Frequently asked questions

Should a night guard go on the top or bottom teeth?

Either works. Upper is the common default; lower is often better for people with gag reflexes, upper restorations, or comfort preferences.

Can I wear both an upper and lower night guard at once?

No, and you should not. One guard creates the protective barrier. Wearing two adds bulk without added protection.

What if I have a retainer and a night guard?

Some people wear a retainer on one arch and a guard on the other. If you need both functions, ask about combined options before doubling up. Our night guard vs retainer guide covers the differences.

Do dentists prefer upper or lower night guards?

Most fit upper guards by default but switch to lower for gag-prone patients or those with upper dental work. It is a judgment call, not a rule.

Remi makes custom night guards for either arch from impressions you take at home, with dentist-grade materials, at about 80% less than a dental office, backed by a 45-night perfect fit guarantee.