How should I care for my mouth and my night guard, and what signs mean I should call the office?

The short version: clean mouth in, clean guard out

A night guard sits over your teeth for roughly a third of every day. Whatever is on your teeth when it goes in, plaque, food debris, sugar from a late snack, stays trapped under plastic until morning, and whatever grows on the guard during the day goes back into your mouth at night. Caring for your mouth and caring for the guard are therefore one routine, not two. The routine below is general education; the dentist who made your guard may adjust it for the material and design you have, so follow the office's instructions where they differ.

Why mouth hygiene matters more when you wear an appliance

Plaque is a sticky film of bacteria that forms on teeth every day. When it is not removed, it irritates the gums, and gingivitis, the early stage of gum disease, shows up as gums that are red, swollen or bleed easily. The acids plaque bacteria produce from sugars also drive tooth decay. Brushing twice a day with a fluoride toothpaste and cleaning between the teeth once a day are the two habits that keep plaque in check, and they matter more, not less, when a guard will hold the teeth in a closed environment for hours.

Saliva is the mouth's own defense: it washes away food, buffers acid and carries the minerals that repair early enamel damage. Many common medications reduce saliva flow. A guard is not usually the cause of dry mouth, but a dry mouth under a guard is a less forgiving place for any plaque that was left behind. If you wake with a dry, sticky mouth, mention it; dry mouth has causes a physician may need to look at, and it changes what your dentist may suggest for home care. The guide on morning jaw soreness and teeth grinding describes what the exam itself may check.

How to clean a night guard

The American Dental Association's advice for mouthguards is a sound starting point for a night guard made from similar materials.

Every night, before it goes in

• Brush and clean between your teeth first. Fluoride toothpaste, a soft brush, and floss or another interdental cleaner, in whichever order you find easiest.
• Rinse the guard under cool running water before you put it in. A guard that has sat in its case all day still collects dust and whatever is in the case.

Every morning, when it comes out

• Rinse it immediately in cool water to remove saliva and loose debris before they dry on the surface.
• Brush it gently with a soft toothbrush, using cool water or a drop of mild dish soap. Some offices prefer a separate brush kept only for the guard and no toothpaste on it; ask what your office recommends for your guard's material.
• Rinse again thoroughly so no soap remains.
• Let it dry before closing the case, unless the office has given different storage instructions for your guard's material. A guard sealed away wet can develop an odor that rinsing alone does not remove.

Once a week

• Give it a longer cleaning. Some offices advise soaking the guard in cool, soapy water for a few minutes; some approve a cleaning tablet made for dental appliances; some advise against tablets for a particular material. Ask the office whether a cleaning tablet is appropriate for your guard, and if so use it as directed on the label.
• Wash the case with soap and water and let it dry open. The case needs cleaning as much as the guard does.
• Look the guard over in good light for cracks, thin or worn-through spots, rough edges and discoloration you cannot clean away. Make a note of anything new so you can show the office.

What to avoid

• Hot water, dishwashers and boiling. Heat can distort a custom guard so that it no longer fits the teeth it was molded to. Rinse and wash in cool water only.
• Sun, hot cars and radiators. The same risk applies to a guard left on a dashboard or a sunny windowsill.
• Bleach and harsh household cleaners. Unless the dentist who made the guard has told you a specific product is safe for its material, assume it is not.
• Soaking in mouthwash without asking first. Appliance materials differ; ask the office before making this a habit.
• Chewing on it, or "adjusting" it yourself. Trimming a sharp edge with scissors or a nail file changes how the bite lands on the guard. Bring it in instead.

What changes the routine

• Soft versus hard guards. The cleaning routine is the same, but soft and hard materials wear differently, so what you look for during the weekly check differs. Ask the office what wear is typical for your guard's material and what would be a reason to bring it in.
• A guard that covers restorations, veneers or implants. Restored teeth and veneers need the same careful daily brushing and flossing as any other tooth, and the gum around an implant can become inflamed just as the gum around a natural tooth can, so it deserves the same daily cleaning. If the guard was made partly to protect this dental work, ask the office to show you the areas that need the most attention before the guard goes in. The guide on whether grinding can damage veneers or crowns explains why that protection matters.
• Dry mouth or medications that cause it. Dry mouth raises the risk of decay and gum problems, and it often has a medical cause. Tell both your dentist and the prescribing physician; the dentist may suggest additional fluoride or other measures, and the physician may be able to review the medication. Do not stop or change a medication on your own.
• Gum recession. Exposed root surfaces are softer than enamel and decay more easily, and a guard edge that rests on receded gum can rub. Use a soft brush, and report any sore spot where the guard edge sits.
• Aligners worn at the same time. Clear aligners and a night guard both cover the teeth but are designed for different jobs, so do not assume one can stand in for the other. If you are in aligner treatment, ask the office how to sequence the two rather than deciding on your own.

Expected versus call the office

A new guard takes some getting used to, and some sensations are normal early on. Others are signals that the guard, the bite or the jaw needs to be looked at. The checklist printed below sets out both columns. The general rule: anything mild that fades within minutes of taking the guard out and settles as you get used to the guard is usually part of adaptation. Anything that persists, worsens, or involves a change in how your teeth meet deserves a call.

A night guard protects the teeth from the forces of grinding; it does not by itself stop grinding, and jaw muscle soreness or headaches that continue despite regular wear are worth reporting rather than waiting out. The guide a night guard protects teeth, but does it stop grinding? explains that distinction, and comparing a custom night guard with a store-bought guard covers why fit matters in the first place.

What an examination determines

When you bring the guard to a check-up, or come in because something has changed, the examination looks at things you cannot easily judge at home:

• Fit. Whether the guard still seats fully on every tooth, rocks, or has become loose or tight after dental work, tooth movement or warping.
• Wear pattern. Where the guard is worn, scratched or cracked shows where and how hard the teeth are meeting at night, and whether the guard is nearing the end of its useful life. There is no fixed replacement schedule; the decision follows the wear, the fit and your symptoms.
• Bite contacts. Whether the teeth meet evenly on the guard, and whether your bite without the guard has changed. A guard should not permanently change the way your teeth fit together; a bite that feels different, or pain that started or increased with the guard, is a reason to stop wearing it until it has been checked.
• Jaw symptoms. Whether soreness, clicking, locking or limited opening point toward an evaluation for a temporomandibular disorder (TMD, a problem of the jaw joint or jaw muscles) rather than a simple adjustment, and whether a different appliance design, or care beyond an appliance, should be discussed.
• Teeth and gums under the guard. Signs of decay, gum inflammation, recession or sore spots in the areas the guard covers.

When it is an emergency instead

Night-guard problems are rarely emergencies, but a tooth or jaw problem can arise regardless of the guard. Breathing or swallowing difficulty, rapidly spreading swelling of the face or neck, fever with facial swelling, uncontrolled bleeding or severe trauma need emergency care: call 911 or go to the nearest emergency department rather than submitting an appointment request. Do not put the guard back in over a broken tooth or a swollen area until it has been examined.

The next step

Bring your guard and its case to your next check-up, and bring the notes from your weekly inspection if anything has changed. If the guard is cracked, no longer fits, or your morning symptoms have changed, request an appointment and describe what you have noticed; a request is not a confirmed appointment, and the team will follow up to schedule it. Occlusal guards, the clinical name for night guards, are among the services this office lists; whether a repair, an adjustment or a new guard is the right step is decided at the examination.