Quick Answer: The safest night guard materials are medical-grade EVA and copolyester. Avoid PVC, latex, or non-medical plastics, which may contain harmful chemicals.
The material your night guard is made from isn’t just about comfort — it’s about safety. High-quality dental plastics like EVA and copolyester are safe for long-term use and provide reliable protection against teeth grinding. But cheaper store-bought guards may use lower-grade plastics, including PVC or latex, which can cause allergies or leach harmful chemicals.
In this article, we’ll break down the most common materials used in custom mouth guards, explain which ones are safe, which to avoid, and why material quality matters for your oral health.
👉 This article is part of our Complete Guide to Night Guard Safety.
Common Materials Used in Custom Mouth Guards
When it comes to custom night guards, not all materials are created equal. The type of plastic used determines how durable, comfortable, and safe your guard will be for long-term wear. Here are the three most common materials you’ll see in high-quality custom guards:
EVA (Ethylene-Vinyl Acetate)
EVA is a soft, flexible plastic that provides cushioning and shock absorption. It’s commonly used for soft guards or the inner layer of dual laminates. When made with medical-grade EVA, it is safe for long-term oral use and free from BPA and phthalates. EVA is a good choice for light grinders or first-time guard wearers who need maximum comfort.
Hard Copolyester (Acrylic-like)
Copolyester is a rigid, durable plastic that offers strong protection against heavy grinding and clenching. Unlike traditional acrylics, Sentinel’s copolyester is BPA-free and non-toxic, making it safer for daily use. Because of its strength, it’s the go-to material for patients with severe bruxism or TMJ who need maximum durability.
Dual Laminate (EVA + Copolyester)
Dual laminate guards combine the best of both worlds: a soft EVA inner layer for comfort and a hard copolyester outer layer for strength. This layered design makes them a popular choice for moderate to heavy grinders who want protection without sacrificing comfort.
💡 Pro Tip: The thickness of the material also matters. A 3mm copolyester guard will last longer than a thinner 1mm style, even when made from the same material.
What Materials to Avoid in Mouth Guards
Not every mouth guard is made with safe, dental-grade plastics. Some cheaper or mass-produced options use lower-quality materials that can pose risks to your health and comfort. Here are the main ones to watch out for:
PVC (Polyvinyl Chloride)
PVC is sometimes used in inexpensive, store‑bought guards because it’s cheap and easy to mold. The problem? PVC may contain phthalates, chemicals linked with potential health concerns, particularly endocrine disruption. It also breaks down more quickly, meaning less protection and more frequent replacements.
Latex Blends
Latex is rarely used in high-quality custom guards today, but it can still appear in cheaper products. The concern is latex allergies, which can cause irritation, sores, or more severe reactions in sensitive individuals. For that reason, latex-containing guards are best avoided altogether.
Non-Medical Grade Plastics
Even when a guard is labeled “custom,” not all plastics are created equal. Lower-grade EVA or acrylic substitutes made overseas may contain unknown additives, dyes, or fillers that compromise both safety and durability. Always look for BPA-free, phthalate-free, FDA-approved materials when choosing a night guard.
💡 Key takeaway: If the material isn’t clearly listed or verified as medical-grade, it’s safer to steer clear.
Why Material Quality Matters for Safety
The type of plastic used in your night guard isn’t just about comfort or durability — it’s about your health. High-quality, FDA-approved materials are tested for biocompatibility (FDA), meaning they’re safe to stay in your mouth for hours every night. Cheaper plastics, on the other hand, may contain additives like phthalates or latex that can trigger allergies or even leach harmful chemicals over time.
Using premium, medical-grade EVA or copolyester also means your guard will last longer, resist warping, and provide consistent protection against grinding forces. By contrast, lower-grade materials tend to wear out quickly, forcing more frequent replacements and leaving your teeth unprotected when they fail.
👉 For a deeper look at material safety, see our Complete Guide to Night Guard Safety.
Custom vs Store-Bought: Material Differences
Not all mouth guards are created equal — and the biggest difference often comes down to the materials.
Store-Bought Guards (OTC / Boil-and-Bite)
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Typically made of low-grade EVA or PVC.
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May contain phthalates or latex (potential allergens).
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Softer plastics often wear out within months and can leach microplastics over time.
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One-size-fits-all design = uneven pressure, reduced protection.
👉 Related: Do Night Guards Leach Microplastics?
Custom-Made Guards (Dentist or Sentinel)
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Crafted from medical-grade EVA and copolyester — BPA-free, latex-free, and FDA-approved.
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Designed to last 1–5+ years depending on the type.
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Evenly distributes bite force, reducing risk of jaw pain and dental damage.
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Precision-fit for safety, comfort, and durability.
👉 Related: How Long Do Dental Night Guards Last?
💚 Key takeaway: Store-bought guards use cheaper plastics that may not be safe for nightly use. Sentinel Mouthguards are made in our FDA-registered U.S. lab with trusted U.S. and German-sourced materials — so you get peace of mind with every wear. Order your custom Sentinel guard today
Store-Bought vs Custom Night Guards: Material Comparison
| Feature | Store-Bought (OTC / Boil-and-Bite) | Custom (Dentist or Sentinel) |
|---|---|---|
| Material Quality | Low-grade EVA or PVC | Medical-grade EVA & copolyester |
| Safety | May contain BPA, phthalates, or latex | BPA-free, latex-free, FDA-approved |
| Durability | 3–6 months (wears down quickly) | 1–5+ years depending on type |
| Fit & Protection | One-size, uneven bite pressure | Precision-fit from dental impressions |
| Comfort | Bulky, often uncomfortable | Slimmer, designed for daily wear |
| Risk of Microplastics | Higher (soft plastics break down) | Minimal (stronger, tested plastics) |
| Cost | $20–$50 | $150–$300 (Sentinel) vs $400–$800 (dentist) |
💚 Key takeaway: Store-bought guards save money up front, but the lower-quality plastics don’t last — and may not be safe for long-term use. Sentinel guards give you dentist-quality protection, made in the USA, at a fraction of the cost. Shop Sentinel Night Guards
Frequently Asked Questions About Mouth Guard Materials
What is the safest material for a night guard?
The safest materials are medical-grade EVA (ethylene-vinyl acetate) and copolyester. These plastics are BPA-free, latex-free, and FDA-approved for long-term oral use. They provide reliable protection while being safe to wear every night.
Are store-bought night guards toxic?
Not all store-bought guards are toxic, but many use lower-grade plastics like PVC or non-medical EVA. These may contain phthalates, latex, or other additives that can irritate the mouth or even leach harmful chemicals over time. For peace of mind, choose a custom guard made with verified safe materials.
Why should I choose BPA-free and latex-free night guards?
BPA and latex have both been linked to health risks and allergic reactions. BPA is a chemical that can disrupt hormones, while latex can cause irritation or severe allergies in sensitive individuals. BPA-free and latex-free guards eliminate these risks, ensuring safe, comfortable use every night.
Conclusion
Not all plastics are safe for nightly use — and that’s why material choice matters. Lower-quality guards made from PVC, latex, or non-medical plastics may be cheap, but they put your health at risk and wear out quickly.
💚 At Sentinel, every guard is crafted from BPA-free, latex-free, FDA-approved materials in our U.S.-based dental lab. That means lasting durability, proven safety, and protection you can trust.
👉 Choose the safer option today — order your custom Sentinel night guard and protect your smile with confidence.