Grinding and Jaw
What does a nightguard actually do?
1 August 2026 · The Dentist, Al Qusais, Dubai
The short answer
A nightguard creates a physical buffer between your upper and lower teeth so that when you clench or grind during sleep, the plastic absorbs the force instead of your enamel. It doesn't cure the habit of grinding, which is usually linked to stress or bite alignment, but it prevents the damage: flattened teeth, cracked fillings, sore jaw muscles and morning headaches. A properly fitted one also spreads the bite load more evenly across your teeth rather than letting a few back teeth take the full force.
The mechanics: what's actually happening in your mouth
When you grind or clench at night, the force going through your teeth can be several times higher than normal chewing. That force has nowhere gentle to go. It travels through the enamel, into the tooth root, and into the jaw joint. Over months and years this shows up as flattened biting edges, small cracks in fillings or crowns, and teeth that become sensitive because the enamel layer has simply worn thin.
A nightguard sits between the upper and lower teeth like a cushion. The plastic absorbs and spreads the impact so it isn't concentrated on the tips of your canines or the ridges of your molars. It also stops tooth-on-tooth contact entirely, which is the main source of the wear. Think of it the way a mouthguard protects a boxer's teeth from a punch: same principle, much lower force, but repeated hundreds of times a night for years.
It manages the damage, not the cause
This is the part people often misunderstand. A nightguard does not stop you from grinding. The grinding itself is usually driven by something else: stress and muscle tension, a bite that doesn't sit together comfortably, certain medications, or in some cases sleep apnoea where the jaw clenches as part of the airway reflex during sleep. If grinding is linked to sleep apnoea, a nightguard alone won't address the underlying breathing issue, and that's worth raising with a doctor as well as a dentist.
What the nightguard reliably does is buy your teeth protection while any underlying cause is being managed, or simply for as long as the habit continues. Many people grind for years without ever fully stopping, and for them the nightguard is the long-term solution: not fixing the habit, but preventing it from costing them their enamel, their fillings or eventually a cracked tooth that needs a crown or root canal.
Why a custom-fitted one works better than a shop-bought version
Store-bought nightguards are boil-and-bite: you soften them in hot water and bite down to shape them roughly to your teeth. They're better than nothing, but the fit is approximate, they're often bulky, and they tend to loosen or wear through within a few months if you grind heavily.
A custom nightguard is made from an impression or digital scan of your exact bite, so it sits precisely on your teeth without needing to be clamped in place by biting hard. That precision matters because a loose guard can actually make clenching worse, as your jaw muscles work harder trying to hold it in place. The material and thickness are also chosen based on how heavily you grind: someone with mild clenching needs something different from someone who's already cracked a molar.
Signs it's time to get checked, and what to do next
If you're waking up with a sore jaw, tension headaches, or a partner has mentioned hearing you grind, it's worth having a dentist look at your teeth for wear facets, small fractures or gum recession near the grinding teeth. These are visible on a straightforward examination and tell us how much protection you actually need.
At The Dentist in Al Qusais, the first checkup is free for new patients, which is a simple way to find out whether a nightguard is advisable and to get a written price before anything is made. If you're already noticing chipped edges or sensitivity, book that check sooner rather than later. Enamel doesn't grow back, so the earlier a nightguard goes in, the less repair work you'll need down the line. You can book online at thedentist.ae/book or message the clinic on WhatsApp to arrange a time that suits you, including evenings or Saturdays.
This article is general information, not a diagnosis. If you are in Dubai, the free first checkup at our Al Qusais clinic is the fastest way to get an answer about your own teeth.