A night guard, formally known as an occlusal splint, is a removable dental appliance worn over the teeth, typically during sleep. Its primary function is to create a protective barrier between the upper and lower dental arches to manage bruxism, which is the unconscious grinding or clenching of teeth. Bruxism generates significant force, leading to dental wear, tooth sensitivity, and damage to dental restorations. The splint works by distributing these forces and allowing the jaw muscles to relax. This relaxation alleviates related symptoms such as jaw tension, headaches, and pain associated with the temporomandibular joint (TMJ). Different types of night guards are available, ranging from over-the-counter options to professionally fabricated devices.
The At-Home Fabrication Process
The most common do-it-yourself option is the “boil-and-bite” night guard, which uses thermoforming to achieve a semi-custom fit. This appliance is typically made from a thermoplastic material, such as ethylene-vinyl acetate (EVA), that softens when exposed to heat. The process begins by boiling water in a pot deep enough to fully submerge the guard. The pot is then removed from the heat, and the guard is submerged for the manufacturer’s specified time, usually 30 to 60 seconds, until the material becomes pliable.
Using tongs, the softened guard is removed and may be briefly dipped in cool water to make the temperature tolerable. The warm guard is quickly placed over the teeth, usually the upper arch, and the user bites down gently but firmly to create indentations. To ensure a snug fit, the user must simultaneously press the material against the outer surface of the teeth and gums with their fingers, while the tongue or a sucking action creates pressure on the inner surface.
This molding action must be maintained for approximately 30 to 60 seconds until the material begins to cool and set. Once the shape is achieved, the guard is removed and placed into cold water for several minutes to fully harden and lock the contour in place. If the edges irritate the gums or cheek, the thermoplastic material can be carefully trimmed with sharp scissors to improve comfort.
Steps for Obtaining a Custom-Fitted Guard
Acquiring a professionally made night guard begins with a consultation to assess bruxism and determine the appropriate splint type. The next step involves taking a precise impression of the teeth and bite using one of two main methods. The traditional approach uses a putty-like material, such as alginate, placed in a tray that captures a negative mold of the teeth. This physical impression is then sent to a dental laboratory.
A modern alternative is the digital impression, which uses an intraoral scanner to create a high-resolution, three-dimensional model of the mouth. Digital scanning is faster and more comfortable, eliminating the potential for gagging associated with putty impressions. The digital file is instantly transmitted to the dental lab, which uses Computer-Aided Design and Manufacturing (CAD/CAM) technology to fabricate the appliance from durable, medical-grade materials.
The dental lab fabricates the guard to the exact specifications of the impression, ensuring proper spacing and alignment. After fabrication, the guard is returned for the final fitting appointment. The dentist checks the fit for security and retention, ensuring it snaps into place without moving. The bite surface is checked using articulating paper to identify uneven points of contact. The dentist makes minute occlusal adjustments by trimming and polishing the material until the jaw closes evenly and comfortably against the guard.
Material Differences and Fit Quality
The effectiveness of a night guard is influenced by the material used and the precision of its fit. Night guards are categorized into three types: soft, dual-laminate, and hard acrylic. Soft guards, typically made from flexible EVA, are recommended for mild clenching or new users due to high initial comfort. However, soft guards wear down quickly under heavy grinding and may sometimes encourage more aggressive clenching.
Hard acrylic guards, fabricated from rigid plastic, are the standard recommendation for moderate to severe bruxism and for managing temporomandibular joint disorders. This material offers superior stability, resists grinding forces, and can be precisely adjusted to achieve a therapeutic occlusal plane that promotes muscle relaxation. The dual-laminate guard offers a compromise, featuring a soft inner layer for comfort and a hard acrylic outer shell for durability.
A precise fit is paramount because an ill-fitting guard can exacerbate oral health issues. An appliance that is too bulky or does not distribute pressure evenly can place unwanted stress on teeth, potentially leading to minor shifting or a change in bite alignment. An uneven surface can also cause unbalanced muscle activation, which may increase clenching and worsen jaw pain. Custom guards minimize these risks by conforming exactly to the dental arch and providing a stable, even surface.
Care and Maintenance Post-Fabrication
Proper daily care is necessary to maintain the hygiene and structural integrity of any night guard. Immediately upon removal each morning, the guard should be rinsed thoroughly under cool or lukewarm water to wash away saliva and debris. Hot water must be avoided, as the heat can permanently warp the thermoplastic or acrylic material, compromising the fit and necessitating replacement.
The night guard should be cleaned daily using a soft-bristled toothbrush and a non-abrasive cleanser, such as mild liquid hand soap. Toothpaste should not be used, as its abrasive particles create microscopic scratches on the surface. These scratches become ideal spots for bacteria and fungi to accumulate. Weekly deep cleaning with specialized denture-cleaning tablets or a diluted vinegar solution helps disinfect the appliance and remove persistent buildup.
After cleaning, the guard must be allowed to air-dry completely before storage. Storing a damp night guard in an airtight container encourages bacterial growth. A clean, well-ventilated storage case is recommended to allow air circulation. The guard should be inspected regularly for signs of deterioration, such as cracks, chips, excessive thinning, or a persistent foul odor, which indicate it is time for replacement.