A night guard, also known as an occlusal splint, is a removable dental appliance worn over the teeth, typically during sleep. Its primary function is to create a physical barrier between the upper and lower teeth, protecting them from bruxism—the involuntary grinding or clenching of the teeth. This protective layer absorbs the intense forces generated during clenching, preventing excessive wear, fractures, and enamel abrasion. While the guard prevents dental damage, misuse or improper fit introduces potential risks to oral health. Whether a night guard can damage teeth depends heavily on the device’s design and how it is used.
Mechanisms of Dental Damage
A poorly fitting or improperly designed night guard can introduce mechanical forces that inadvertently cause structural and positional changes in the mouth. One significant risk is occlusal changes, or bite shifting, where continuous, uneven pressure on certain teeth causes minor movement over time. If a guard does not distribute the bite force equally across the arch, it concentrates pressure on a few teeth, potentially leading to misalignment. Soft, pliable materials found in some guards can exacerbate this shifting by encouraging the jaw muscles to clench more intensely.
Another concern is soft tissue irritation, which occurs when the edges of the guard press into the gums or cheek tissue. An ill-fitting appliance creates chronic pressure points that lead to gum recession, localized inflammation, or painful sores. This irritation compromises the health of the gingival tissue, making teeth more vulnerable to other issues. Furthermore, an improperly constructed guard can aggravate the temporomandibular joint (TMJ) if it forces the jaw into an incorrect resting position.
A night guard that is not properly cleaned or maintained presents a significant risk for accelerated tooth decay and demineralization. The appliance traps saliva, plaque, and acidic byproducts of bacteria directly against the tooth surface throughout the night. If a person fails to clean both their teeth and the guard thoroughly before use, this trapped environment becomes an ideal incubator for harmful bacteria. This constant exposure to bacteria and acid increases the likelihood of developing cavities and gum issues.
Custom Fit Versus Over-the-Counter Devices
The largest factor determining a night guard’s safety profile is the precision of its fit, distinguishing custom and over-the-counter (OTC) devices. Custom night guards are made from a detailed impression of the patient’s mouth and fabricated in a dental lab. This process ensures the guard conforms perfectly to the unique contours of the teeth and gums, maximizing comfort and stability. Custom guards use high-quality, durable acrylics that provide a stable, even surface for the opposing arch to contact.
The precise, lab-created fit of a custom guard distributes the immense pressure of clenching evenly across the dental arch, minimizing the risk of bite changes or tooth movement. Dentists adjust these guards to ensure the jaw rests in a correct, comfortable position, reducing strain on the temporomandibular joint. This professional supervision and tailored design directly mitigate structural and positional damage.
In stark contrast, OTC guards, such as “boil-and-bite” or one-size-fits-all options, cannot achieve this level of precision. While inexpensive and convenient, their generic nature means they are often bulkier and less comfortable, relying on the user to achieve a partial fit. The lack of a precise fit is the primary precursor to damage, as these guards are prone to uneven contact, causing isolated pressure points and potential shifting. Softer OTC materials can compress easily, potentially encouraging the clenching behavior they are meant to treat, or they may wear out quickly. The risk of causing unintended dental issues increases significantly when using a non-custom device without professional oversight.
Maintenance and Usage Protocols
Even a perfectly fitted custom guard requires diligent maintenance and adherence to usage protocols to prevent damage from hygiene issues or material distortion. The guard must be cleaned immediately after removal each morning to prevent the adherence of plaque and debris. Cleaning involves gently brushing the appliance with a soft-bristled brush and cool water, often using a mild, non-abrasive soap or specialized cleaner. Many toothpastes are too abrasive and can scratch the material, creating microscopic havens for bacteria that promote decay.
Proper storage is necessary to preserve the guard’s precise fit and prevent warping. The appliance should never be exposed to heat, such as hot water, direct sunlight, or a clothes dryer, as heat can deform the plastic and render the guard ill-fitting. After cleaning, the night guard should air-dry completely before being placed in a clean, ventilated storage case. Storing a damp guard in an airtight container creates a moist environment that encourages the growth of bacteria and mold.
Regular professional assessment is a non-negotiable part of using a night guard for long-term safety. Patients should bring their guard to every dental check-up so the dentist can inspect it for signs of wear, cracks, or distortion. The dentist confirms that the appliance is still fitting correctly and is not causing any subtle, unwanted bite shifts over time. A night guard typically lasts three to five years, but it should be replaced sooner if it shows significant wear or no longer fits snugly, as a damaged guard loses its protective function.