From Aligner to Retainer: Could the Last Invisalign Aligner Replace an Invisalign Retainer?

One of the most common questions asked by dental patients about to finish a course of Invisalign is whether or not they can use their final aligner as a retainer. After all, Invisalign aligners and retainers look almost identical. Invisalign retainers, known as Vivera retainers, are also composed of the same medical grade polymer. Telling one apart from the other then can be difficult.

However, while it is possible for the last Invisalign tray in a course to serve as your retainer, there are certain differences which must be taken into account. Because of these differences, an Invisalign aligner should be used for the purposes of retention on a temporary basis.

The Plastic of Vivera Retainers is Thicker

Though the two are made of thermoplastic, Vivera retainers are thicker and are therefore sturdier and less prone to breakage or wear and tear.

Vivera Retainers are More Rigid

Because Invisalign aligners are designed to gently move teeth in a required direction, they are less rigid than Vivera retainers. Rigidity is ideal for holding teeth in position.

Aligners Were Designed to Last Two Weeks

Each Invisalign tray, regardless of its order in the queue, was designed to last the two weeks that it takes to move your teeth to the next position. If you do decide to use an aligner as a retainer then, be prepared for some staining and wear and tear further down the road.

Invisalign Aligners Might be Helpful as Overnight Retainers

The most common use for the last Invisalign tray in a course is as an overnight retainer to be worn while you are sleeping. However, as mentioned earlier, Invisalign trays are weaker and more prone to wear and tear than Vivera retainers, therefore this should only be a temporary measure, perhaps while you save up to purchase a retainer.

Always Keep Hold of Your Last One or Two Aligners

Whatever your plans are post Invisalign treatment, it is always a good idea to keep hold of at least your last two trays. Doing this helps you in two ways. If you are using a Vivera retainer but for some reason don't wear your retainer for a prolonged period of time, your teeth could shift back towards their old positions. If the change is considerable, your retainers may not be suitable for returning those teeth to their ideal positioning. It also may be extremely painful to try to do so.

In that case, you can use your last two Invisalign trays to return your teeth to a more favourable position before using your retainer to keep them in place. For example, if you notice your teeth have shifted, simply wear your second to last or last tray for a few days until your teeth shift back to their former post-Invisalign position. And by keeping your last two Invisalign trays, you'll be able to use them as temporary retainers should you misplace your Vivera retainer in future.

Talk with an orthodontist if you have questions about keeping your teeth perfectly straight.