Want to clean a retainer or mouthguard, but unsure whether to soak it for 5 minutes or 3 hours? Start with whether your appliance allows this cleaner and the time out of your mouth. Then choose the labelled purpose and finish with a thorough rinse. The guide below puts those decisions in order.
I’m Irene, a Taiwan-born pharmacist qualified in Japan. This guide uses Kobayashi’s Japanese product-detail page for ピースクリン マウスピース洗浄剤 (Peaceclin Mouthpiece Cleaner), 2.0 g × 48-tablet specification. It is not a hands-on cleaning test.
- Before soaking: match the pack and check your appliance
- 5 minutes or 3 hours: choose by purpose
- Once the checks pass, finish all three steps
- If dirt remains, do not automatically reach for a toothbrush
- If you see 2.6 g or 40–50°C, compare the actual label
- Keep both tablets and solution out of your mouth
- Finding the pack in Japan
- Sources and scope
Before soaking: match the pack and check your appliance
Check your pack’s tablet weight, count and back-label directions, not just the blue box or barcode. This guide uses the 2.0 g × 48-tablet specification on Kobayashi’s product-detail page; it has not verified every production batch or your individual pack. If your label differs, compare the label before using these numbers.
The Japanese word マウスピース covers appliances with different uses. A clear appearance does not establish compatibility. Check the appliance maker’s guidance and your dentist’s instructions for all three points:
- Cleaner and material: is this type of soaking tablet allowed? For special materials, including soft ones, Peaceclin requires prior dental advice.
- Water temperature: what does your appliance allow? The cleaner’s directions do not override a stricter appliance limit.
- Time out of your mouth: can you complete the chosen soak and rinse without reducing prescribed wear time?
Not compatible, or not sure? Do not use this cleaner yet. Ask the appliance maker or your dentist; a claim that the product is for “mouthpieces and retainers” is not approval for every clear-aligner brand.
This is for a removable appliance cleaned in a container outside your mouth, not fixed braces or direct use in the mouth.
5 minutes or 3 hours: choose by purpose
Choose the purpose → read that time → check whether it fits.
Based on the 2.0 g × 48-tablet specification on Kobayashi’s product-detail page; still check your actual pack.
Cleaning dirt after a meal?
5 minutes The official product-detail page’s after-meal cleaning instruction.
Not a 99.9% bacterial-reduction claim. It does not replace the longer soak for the purposes on the other branch.
Deodorizing, bacterial reduction, bleaching or plaque removal?
3 hours The official product-detail page’s instruction for these longer-soak purposes.
The 99.9% bacterial-reduction claim is from Kobayashi’s own 3-hour test. It does not cover all bacteria or guarantee sterilization.
Cannot fit the chosen time around prescribed wear? Do not use this soak for that purpose now. If 3 hours is not possible, 5 minutes is not a substitute for the longer-soak purposes. Ask your dentist about a suitable cleaning arrangement; do not shorten prescribed wear time.
Only if your appliance is compatible, the label matches and the timing fits → follow the three steps below.
Once the checks pass, finish all three steps
Prepare → immerse → rinse and discard
Only for the official product-detail page’s 2.0 g × 48-tablet directions, after the checks above.
Prepare the solution
150–180 mL water + 1 tablet
Use water, or warm water at about 40°C only if your appliance permits it. Open the individual wrapper just before use.
No water at approximately 50°C or above for mouthpieces and retainers. Below 50°C is not automatically safe; follow any stricter appliance limit.
Immerse immediately
Put the removed appliance into the solution straight away, then soak for the 5 minutes or 3 hours selected by purpose above.
Keep the tablets and solution out of your mouth and eyes, and away from children and people who need supervision.
Rinse thoroughly, then discard
Rinse the appliance thoroughly with water before putting it back in your mouth. Discard the remaining solution after every use; do not save it for the next soak.
If dirt remains, do not automatically reach for a toothbrush
Peaceclin specifically says not to brush silicone-rubber appliances, because brushing may scratch them. For other materials, check the appliance maker’s permitted care method rather than treating brushing as a universal rule.
Persistent staining or odour may need a dentist’s assessment for long-standing pigment deposits or tartar. Stop using the product and consult your dentist if the appliance changes colour, deforms or shows other abnormalities. Even though the official product-detail page lists an ingredient intended to help prevent metal discoloration, the manufacturer still notes that some metals may rarely discolour.
If you see 2.6 g or 40–50°C, compare the actual label
When checked on 29 October 2026, the Japanese product-detail page listed the 48-tablet specification as 2.0 g and about 40°C. The Japanese brand page also displayed instructions with 2.6 g and 40–50°C. The reason and chronology of this difference were not established, so they cannot reliably be called old and new versions.
This guide uses only the 2.0 g × 48-tablet specification and figures on the product-detail page described above; it does not combine the two sets of directions. If your tablet weight, temperature or other instructions differ, do not copy this guide’s numbers. Check your actual pack and ask Kobayashi about unresolved product-label questions; ask the appliance maker or your dentist about compatibility. Overseas-market directions and translated shop summaries are not substitutes for your Japanese pack’s label.
Keep both tablets and solution out of your mouth
This is an oral-appliance cleaning product, not mouthwash or medicine. Do not put the tablets or solution in your mouth or eyes. Keep the product and prepared solution out of reach of children and people who need supervision. If accidental eye or mouth exposure occurs, follow the full first-aid instructions on the pack or official page; seek medical attention when needed and take the product with you.
Finding the pack in Japan
Look for the Japanese name ピースクリン マウスピース洗浄剤 and read the back label. Before buying, confirm availability and price with the shop, and check the actual 48-tablet pack again.
Product identification photo retained as the article’s cover: from Kobayashi’s official product page; the original-photo link is listed below. Copyright and trademarks belong to their respective owners; the photo does not imply endorsement of this article. The diagrams here organize the labelled decisions and steps; they are not test results.
Sources and scope
- Kobayashi: product details, 2.0 g specification, timings, water quantity and precautions
- Peaceclin brand page: the specification difference explained above, not interchangeable directions
- Kobayashi: original product-identification cover photo
Official product-detail and brand pages rechecked 29 October 2026. This guide is based on official web information, without purchasing a sample, verifying its production batch or testing cleaning performance. The official photograph is for product identification. Follow your actual cleaner label, your appliance maker’s guidance and your dentist’s instructions together.
