My Retainer Does Not Fit: What Should I Do?

If your retainer will not fit properly or causes pain, do not force it onto your teeth. Contact your orthodontist to find out whether the problem is the appliance, a change in tooth position, or something else that needs attention. Buying another retainer is not always the first step.

A change in fit needs an explanation

A retainer can feel different if your teeth have moved or the appliance has changed shape. The American Association of Orthodontists recommends professional evaluation when a retainer does not fit or is painful. A replacement may be appropriate, but some situations need orthodontic treatment instead. Read the AAO's guidance on a tight retainer.

Describe what you notice without trying to diagnose it. “It feels tight” is useful; “the upper retainer lifts at the back and hurts when I press it down” gives the office more specific information.

Gather these details before you call

• Which retainer: upper, lower, or both; a new set or one you have worn before.
• When it last fit comfortably: include any break in your usual wear routine.
• What changed: tightness, looseness, a visible gap, rocking, or pain.
• What happened recently: mention dental work, a drop, heat exposure, or visible damage.
• What you have available: tell the office if you have a spare, and ask whether to use it.

A simple message could be: “My lower retainer fit last week. Today it will not sit down at the back. I have not tried to force it. Can you advise what I should wear and whether I need a fit check?” This is an example message, not a customer review.

Avoid trying to reshape it at home

Do not use hot water to soften a retainer into place. Heat can warp plastic and change its fit, according to the AAO's retainer care guide. If you see cracks or warping, stop using the damaged appliance and contact your orthodontist. Our hot-water guide explains that care mistake in more detail.

Ask for a wear plan while you wait for advice rather than deciding to press harder, reshape the retainer, or abandon retention indefinitely. Keep the appliance in its case so you can bring it to an appointment if requested.

When a replacement is the right next step

Once you know that replacement retention is appropriate, compare your options. Retainers maintain tooth position; they are not teeth-straightening treatment. A new retainer should not be ordered with the expectation that it will move teeth back to where an old set fitted.

Mavira's Custom Clear Retainer Kit uses impressions you take at home. You return them in the prepaid mailer, and the lab makes your custom retainers. Review the Mavira retainer packages after any fit or clinical concern has been assessed.

If your question is mainly about a gap in wearing your retainer, our guide to time without a retainer provides additional context. Your orthodontist's instructions should guide your own routine.