It depends on the crack. A tiny surface line that doesn’t change the fit may be okay short-term. But if the crack goes through the plastic, creates a sharp edge, or makes the retainer loose, it’s no longer doing its job and can irritate your gums or cheeks. Get a replacement soon so your teeth don’t shift.

A cracked retainer is best replaced, not repaired at home.
FixUrSmile makes custom clear retainers from impressions you take at home: $145 per arch or $265 for both. Keeping a spare set means one crack doesn’t leave you without a retainer. See retainer replacement and retainer cost.
A tiny crack that doesn’t change the fit or create a sharp edge may be okay short-term, but replace it soon. Stop wearing it if it’s loose or sharp.
It’s not recommended. Household glues aren’t safe for the mouth, and patched retainers rarely fit correctly.
It varies. Some people notice changes within days or weeks, especially soon after treatment. Replace a broken retainer as quickly as possible.
Remove it evenly from both sides, keep it away from heat, store it in its case, and consider a night guard if you grind.
Custom clear retainer, $145 per arch. Made in our US dental lab from impressions you take at home, with licensed dentist approval and our Custom Fit Guarantee.
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