Night Guard

A night guard (also called an occlusal splint, bite guard, or bruxism appliance) is a custom-fabricated oral appliance worn during sleep to protect the teeth, jaw joints, and muscles from the effects of bruxism — habitual grinding or clenching of the teeth.

Why Night Guards Are Prescribed

Bruxism affects a significant portion of the adult population and can cause:

• Tooth wear — Grinding progressively flattens occlusal surfaces, shortens teeth, and can expose dentin
• Tooth fracture — The forces generated during clenching can crack natural teeth, restorations, and crowns
• TMJ discomfort — Sustained muscle tension and joint loading contribute to jaw pain, clicking, and limited opening
• Headaches — Bruxism-related muscle tension often presents as morning headaches or facial soreness
• Damage to existing dental work — Crowns, bridges, and veneers are vulnerable to bruxism forces

A night guard doesn’t stop bruxism — the grinding and clenching still occurs — but it separates the teeth and distributes the forces, preventing direct damage.

Types of Night Guards

Hard (Rigid) Night Guards

Made from heat-cured or cold-cured clear acrylic, hard night guards are the most commonly prescribed type. They provide a rigid, durable surface that:

• Distributes clenching forces evenly
• Prevents tooth-to-tooth contact
• Can be adjusted for proper occlusal contacts
• Lasts 2–5 years with proper care

Hard guards are typically fabricated for the upper arch, though lower arch guards are used in some cases.

Soft Night Guards

Made from flexible thermoplastic material (EVA), soft guards offer a cushioning effect. They’re sometimes preferred for mild bruxism or patients who find hard guards uncomfortable. However, soft guards can actually stimulate clenching in some patients and tend to wear out faster.

Dual-Laminate Guards

These combine a soft inner layer (for comfort) with a hard outer layer (for durability and force distribution). They offer a compromise between comfort and function.

Lab-Fabricated vs. Over-the-Counter

Custom lab-fabricated night guards are made from accurate impressions of the patient’s teeth, ensuring precise fit and proper occlusal contacts. Over-the-counter boil-and-bite guards are a low-cost alternative but typically lack proper fit, inadequately distribute forces, and may even worsen TMJ symptoms by positioning the jaw incorrectly.

For patients with significant bruxism, a custom-fabricated night guard from a dental lab is the standard of care.

Prescribing a Night Guard

When ordering a night guard from your lab, specify:

• Upper or lower arch
• Material — hard, soft, or dual-laminate
• Thickness — typically 2–3mm for hard guards
• Coverage — full arch is standard; specify if partial coverage is desired
• Occlusal scheme — flat plane, canine guidance, or balanced contacts

Include a clear impression of both arches and a bite registration so the lab can articulate the models correctly.