What Materials Are Safe and Hygienic for Dental Stickers?

I. Core Base Material: Medical-Grade Resins (Preferred Mainstream Option)

Resin materials are the primary base for dental stickers due to their high moldability, transparency, and ability to conform closely to tooth contours. The key factor for safety lies in meeting medical-grade standards, rather than using ordinary industrial resins.

Medical-grade acrylic resins are the preferred base material. They comply with ISO 10993 oral biocompatibility standards, contain no formaldehyde, benzene, or other toxic volatile substances, and are non-irritating when in contact with tooth surfaces and gums. They are also resistant to saliva corrosion and unlikely to degrade or deform in the oral environment. After high-temperature curing, the resin surface becomes dense and smooth, making it difficult for food debris and bacteria to adhere. Daily hygiene can be maintained through regular tooth brushing alone.
Most compliant products on the market use imported medical resins, often derived from composite resins commonly used in dental restorations. These materials combine flexibility and wear resistance, adapt well to different tooth curvatures, are unlikely to detach during wear, and help prevent scratching or damaging tooth enamel.

In contrast, ordinary ABS or industrial resins should be avoided. These materials are not medically certified and may contain plasticizers, heavy metals, or other harmful substances. Prolonged exposure to saliva can lead to slow toxin release, potentially causing gum swelling, halitosis, or even enamel damage. Inferior resins also tend to have rough surfaces that promote bacterial growth, disrupt the oral microbiome, and increase the risk of gingivitis.

II. Adhesive Layer Material: Medical-Grade Pressure-Sensitive Adhesives (A Critical Hygiene Factor)

The adhesive layer comes into direct contact with the tooth surface, making its safety and adhesion balance essential. Medical-grade, low-irritation, residue-free adhesives are required to avoid enamel damage or allergic reactions.

Medical-grade silicone pressure-sensitive adhesives are the most widely accepted safe option. They offer excellent biocompatibility, moderate and stable adhesion, easy removal without residue, and strong resistance to saliva immersion. These adhesives do not degrade or release harmful substances in the moist oral environment and are commonly used in temporary dental restorative materials. They are non-corrosive to enamel and require no polishing or aggressive cleaning after removal, making them ideal for short-term use.
Some high-end products use modified acrylic pressure-sensitive adhesives with added antibacterial agents, further reducing bacterial growth while improving adhesion stability and minimizing the risk of detachment during eating.

Industrial adhesives and low-quality glues must be strictly avoided. They often contain irritating substances such as formaldehyde resins and toluene, which can emit strong odors, penetrate enamel microgaps, cause tooth sensitivity and gum inflammation, and leave residues that are difficult to remove. Over time, these residues can contribute to plaque and tartar buildup. When assessing adhesive safety, products clearly labeled “dental-use adhesive” or “residue-free” should be prioritized.

III. Decorative Layer Materials: Food-Grade Pigments and Coatings (Avoiding Heavy Metal Risks)

The decorative appearance of dental stickers depends on surface pigments or metallic coatings, which must meet food-grade standards to prevent heavy metal contamination or pigment shedding that could lead to oral ingestion of harmful substances.

Food-grade inorganic pigments are the safest choice, such as titanium dioxide (white) and iron oxide pigments (reds and browns). These pigments are non-toxic, highly stable, and resistant to saliva exposure and friction. They comply with GB 2760 food additive standards and pose no risk even if they come into brief contact with oral mucosa. Some premium products use dental-specific color pastes derived from restorative materials, offering natural coloration with excellent wear resistance while maintaining high safety standards.

For metallic finishes, dental stickers should use electroplated pure gold, pure silver, or medical-grade stainless steel coatings, all of which offer good biocompatibility and resistance to oxidation. Inferior coatings such as nickel alloys or chrome plating should be avoided, as nickel is a common allergen in both skin and oral tissues, and low-quality coatings may flake off, be accidentally ingested, or irritate the gums. Decorative layers containing fluorescent agents or industrial dyes should also be avoided due to their potential to cause oral mucosal irritation and long-term health risks.

IV. Special Materials: Natural Extract-Based Substrates (For Sensitive Users)

For individuals with sensitive gums or a higher tendency toward allergies, some brands offer dental stickers made with natural extract-based substrates, designed to further reduce irritation while maintaining hygiene.

Composites made from natural rubber and plant fibers provide softness, breathability, and low allergenicity, making them suitable for users with fragile gums or sensitive teeth. These materials typically lack chemical surface coatings, rely on natural resin bonding, and are biodegradable, offering environmental benefits as well. Some formulations include natural additives such as menthol or honeysuckle extract, which can help relieve mild gum discomfort and provide antibacterial effects, reducing oral odor. However, products should be free from artificial fragrances and alcohol to avoid counterproductive irritation.

The main limitation of natural materials is their relatively weaker adhesion and lower wear resistance, resulting in shorter wear durations (typically 1–2 days). From a hygiene and safety perspective, they are best suited for short-term, low-frequency use and should be removed promptly after use to prevent bacterial growth due to material aging.

V. Core Principles and Precautions for Safe and Hygienic Material Selection

When choosing materials for dental stickers, three core principles should always be followed: medical-grade or food-grade certification, low irritation, and ease of cleaning. Consumers should review product testing reports and confirm compliance with national medical device registration requirements or certifications such as FDA approval, with clearly disclosed material compositions. Unlabeled or uncertified products should be avoided.

Before application, teeth should be thoroughly cleaned to remove food residue and reduce bacterial growth. If symptoms such as gum redness, swelling, tooth sensitivity, or discomfort occur during wear, the sticker should be removed immediately and potential material allergies assessed.

Regardless of material safety, long-term continuous wear of dental stickers is not recommended. Prolonged coverage of tooth surfaces can interfere with normal cleaning, leading to plaque accumulation and potential enamel damage. After short-term use, teeth should be cleaned thoroughly to maintain oral hygiene and minimize health risks associated with both materials and wearing practices.