Last updated: November 10, 2026.

Impression Kit Instructions & Safety

This page is part of the Terms of Service of Alienguards, LLC, 25 S 3rd St, Unit 105, San Jose, CA 95113. Questions: support@alienguards.com.

Read this entire page before you open or use an impression kit. If a printed insert that ships with the kit is more specific about materials or timing, follow the insert for those details and follow this page for warnings and eligibility.

Warning: choking and swallowing hazard

Impression putty, trays, completed impressions, and a loose or broken mouthguard can be a choking and aspiration hazard. Do not swallow putty or tray pieces. Do not leave putty, trays, impressions, or guards where children or pets can reach them. Use the kit only while awake and seated, never while lying down, walking, or in a moving vehicle.

If putty, a tray, a piece of an impression, or a piece of a guard is swallowed or inhaled, or if a person cannot breathe, coughs persistently, or starts to turn pale or blue, call emergency services immediately (in the United States, 911). We are not an emergency service.

Warning: allergy and irritation

Impression materials and mouthguard plastics can cause irritation or allergic reaction in some people.

Do not use the kit if you or the person being impressed has a known allergy to the materials listed for your kit, or a history of severe reactions to dental impression materials. If you are unsure, ask a dentist or physician before proceeding.

Stop immediately if you feel burning, itching, swelling, rash, dizziness, or shortness of breath. Remove the tray if you can do so safely, rinse the mouth with water, and seek medical care. For trouble breathing or swelling of the lips, tongue, face, or throat, seek emergency care.

Mild, short-lived gagging or a strange taste can occur. If gagging is severe, remove the tray and pause. Do not force a tray into place.

Supervise minors; age

A person under 18 may use a kit only if a parent or legal guardian has purchased it, has agreed to the Terms of Service and Assumption of Risk and Release, and is present and supervising the entire impression process and the first fitting of the guard. Do not allow a child to mix or handle putty unsupervised. Keep all kit contents and finished guards out of reach of young children when not in use. This kit is not a toy.

Who should not use the kit without a dentist’s guidance

Do not use the kit, and talk to a dentist first, if the person being impressed has any of the following, unless a dentist has told you it is appropriate: active sores, abscesses, unusual swelling, or an untreated oral infection; recent oral surgery, extractions, or dental work that has not fully healed; loose teeth, loose crowns or bridges, or orthodontic hardware that could be pulled or damaged; a severe gag reflex, difficulty breathing through the nose, or an inability to sit still for the working time of the material; or any condition that makes it unsafe to have a tray in the mouth without professional supervision. This list is a safety screen, not a diagnosis.

Before you start and taking the impression

Follow the times and material steps on the printed insert that ships with your kit.

1. Read every step, set out the kit pieces, and wash and dry your hands. Remove removable appliances and food from the teeth.
2. Mix the putty as the kit insert directs, for the stated number of seconds only. Do not add water, oil, or other substances unless the insert says to.
3. Load the tray quickly and evenly, without leaving large gaps or overfilling so that material flows down the throat.
4. Seat the tray with steady pressure. Breathe through the nose. Do not talk, chew, or shift the tray once it is seated. Leave it in place until the material has fully set for the time stated in the insert.
5. Remove the tray with even pressure and check that tooth indentations are clear and not torn. Repeat for the other arch if required. Do not reuse mixed putty.
6. If you are unsure whether an impression is usable, photograph it and email support@alienguards.com before you mail it.

Pack and mail the impression as the kit describes. Do not bake, boil, or freeze it. Dispose of leftover mixed material in the trash, not down the sink, and out of reach of children and pets.

When your mouthguard arrives

Inspect it before the first use. Do not use it if it is cracked, has sharp unintended edges, or does not match the order. Follow any wear-and-care card that ships with it. Rinse it before and after use as directed. Inspect the guard before each use. Do not use it if it is worn, cracked, loose, or no longer fits. Do not chew it. Replace it when worn or damaged, and about once a year or sooner if teeth have changed, or as a dentist or trainer advises. Stop use if you have irritation or any of the symptoms listed in the Medical & Product Disclaimer, and contact a dentist and us.

See the Refund & Remake Policy, Medical & Product Disclaimer, and Assumption of Risk and Release.