Sleeping with a mouth guard is a common practice recommended by dental professionals, and for the vast majority of users, these devices are safe and beneficial. A sleeping mouth guard, often called a night guard or dental splint, is a custom-fitted or over-the-counter appliance worn over the teeth during sleep. The primary function is to protect the teeth and jaw from damaging forces that occur unconsciously at night. While generally safe, the potential for complications arises when a guard is ill-fitting, improperly used, or not cleaned correctly, which is why understanding the device is important before beginning use.
Understanding Why Mouth Guards Are Used
These dental appliances are primarily prescribed as a defensive treatment against nocturnal bruxism, which is the involuntary clenching or grinding of teeth during sleep. Untreated bruxism can cause significant damage, leading to worn-down enamel, chipped teeth, and even fractures. The guard creates a physical barrier that absorbs and distributes the destructive forces of grinding, protecting the tooth structure from wear.
Mouth guards are also a common intervention for symptoms associated with temporomandibular joint disorder (TMD), a condition affecting the jaw joints and surrounding muscles. By preventing the upper and lower teeth from meeting, the guard helps the jaw muscles relax, often alleviating morning headaches, facial pain, and jaw soreness. Furthermore, a specific type of oral appliance, known as a mandibular advancement device (MAD), is used to treat mild to moderate obstructive sleep apnea (OSA) by gently shifting the jaw forward to keep the airway open.
Specific Risks Associated with Sleeping Guards
While beneficial, the use of a sleeping mouth guard is not entirely without risk, especially if the device is not professionally monitored. One of the most common concerns is the potential for unwanted dental changes or bite misalignment with long-term use. If a guard is poorly designed, it can apply uneven pressure, leading to subtle or even noticeable shifts in tooth position over time, which can sometimes result in an open bite where the front teeth no longer touch.
Airway issues are another serious, though rare, concern, particularly when a guard is ill-fitting and obstructs airflow rather than improving it. For individuals with undiagnosed or severe sleep apnea, using a standard night guard not designed to reposition the jaw can exacerbate the condition by allowing the tongue to fall backward. Loose or severely worn-down appliances also carry a slight risk of becoming dislodged and posing a gagging or choking hazard during sleep.
Hygiene is a substantial risk factor, as the warm, moist environment of the mouth allows bacteria, yeast, and mold to thrive on the guard’s surface. A poorly cleaned appliance can harbor these microorganisms, leading to gum irritation, periodontitis, or oral thrush. Exposure to a contaminated guard can also contribute to bad breath and material breakdown.
The Difference Between Custom and Over-the-Counter Guards
The safety profile of a sleeping mouth guard is heavily influenced by whether it is a custom-fitted device or an over-the-counter (OTC) option. Custom-fitted guards are fabricated by a dentist using a precise mold of the patient’s teeth and are designed to distribute pressure evenly across the dental arch. This precision ensures a secure fit, maximizes comfort, and significantly reduces the likelihood of causing adverse bite changes or gum irritation.
In contrast, OTC guards, often of the “boil-and-bite” variety, are a one-size-fits-most solution. These devices are typically bulkier and less retentive than custom options, making them more prone to shifting or dislodging during the night. Their poor fit can create inconsistent pressure points, increasing the chance of minor tooth movement or jaw misalignment over extended periods. Furthermore, OTC materials are generally less durable and may degrade more quickly than the medical-grade materials used in a professionally made device.
Maintaining Safety and Knowing When to Seek Professional Guidance
To minimize risks, consistent and correct maintenance is necessary. The appliance must be cleaned daily using a soft toothbrush and mild soap or a specialized cleanser, never abrasive toothpaste, to prevent the buildup of harmful bacteria and fungi. After cleaning, the guard should air-dry completely before being stored in a ventilated case, as moisture encourages microbial growth.
Users should proactively monitor the condition of the guard and their oral health, seeking professional guidance if any warning signs appear. Immediate consultation is warranted if the guard feels loose, warped, or cracked, as a compromised device is no longer fully protective and may become a hazard. Persistent jaw pain, new or worsening symptoms of sleep-disordered breathing, or any noticeable change in how the upper and lower teeth meet should prompt a visit to a dentist or sleep specialist. Individuals with severe TMJ pain or diagnosed, untreated sleep apnea should use any oral appliance only under professional supervision.