Straight teeth in just six months: That’s the claim that has overrun billboards and brick walls in big cities, promising busy people that they can get the smile of their dreams without a single visit to an orthodontist.

If that sounds too good to be true, it might be — for some people. While invisible braces certainly work for many people, the rise in popularity and the promise of convenience has people who really need traditional orthodontic treatment opting for mail-order aligners.

In this guide, take a look at the different brands of invisible braces available, how they work, and whether you should really see an orthodontist before spending a couple thousand dollars on Invisalign-style tooth trays. Spoiler alert — you should.

What are invisible braces?

“Invisible braces” is the common vernacular for what’s really called “clear aligners.” It’s also common for people to refer to all clear aligners as Invisalign, which is a brand name that has become a common term, like Windex and Kleenex.

Invisible braces do the same thing as traditional metal braces — slowly adjust teeth to straighten them and fix bite problems — except they’re clear, made of plastic and are removable. You can take them off to eat and brush your teeth, and you’ll never cut the inside of your cheek on a sharp metal bracket (something all braces-wearers know too well).

Most direct-to-consumer clear aligners involve a mail-order impression kit. You send the impression kit back to the company, where dentists or orthodontists analyze it and create your custom set of clear aligners based on its analysis of your teeth.

Where to get mail-order clear aligners

In a world where you can get birth control online, take a hormone panel through the mail and even get a medical diagnosis through your phone, it should come as no surprise that several mail-order invisible braces companies now exist. Here are five places to get clear aligners without visiting an orthodontist.

What about Invisalign?

You might be wondering why Invisalign, arguably the most popular provider of clear aligners, isn’t on this list. That’s because Invisalign isn’t a direct-to-consumer company, so you must go through an orthodontist to get fitted for and treated with Invisalign. You also have to attend periodic check-up appointments at your orthodontist’s office with Invisalign.

Those are drawbacks if you’re looking purely for mail-order clear aligners that allow you to complete treatment at home, but the Invisalign route does offer some benefits.

For example, regularly seeing an orthodontist ensures that your clear aligners are working like they’re supposed to and that you’re on track for straighter teeth. Your orthodontist can also check for any new issues that arise, such as a gap introduced by the aligners or gum erosion.

Who should get clear aligners?

Speaking of seeing an orthodontist, clear aligners aren’t for everyone and they can’t treat everything. Most clear aligners can treat overbite, underbite, crossbite, open bite, small gaps and crowded teeth to a certain extent.

If you have a severe case of any of these conditions, such as a gap wider than two millimeters, your orthodontist might recommend traditional braces. Other situations where clear aligners might not be right for you include:

• Tooth rotation: If your tooth is rotated because of crowding, clear aligners may not be able to rotate the tooth into the right position.
• Intrusion: Clear aligners can’t fix a tooth that is jammed into the jawbone.
• Extrusion: A tooth that sits high on the bone and is taller than other teeth can’t be fixed with invisible braces.
• Misshapen teeth: If you have teeth that are rounded, pointy or pegged, clear aligners may not fit them properly.
• Midline movement: If your teeth don’t match the imaginary line that bisects your face (your midline), clear aligners may not correct the discrepancy if it’s more than two millimeters on either side.

If you have any of the above conditions, it’s best to see an orthodontist before trying any brand of clear aligners. Even if you don’t have (or don’t think you have) any of these orthodontic complications, it’s still worth seeing a professional before starting treatment. An orthodontist can spot issues that you cannot, and so it’s best to be evaluated in-person before using at-home aligners.

You may have a now-unnoticeable condition that could be aggravated by clear aligners; something that only a trained specialist would be able to inform you of at an in-person appointment. For instance, the orthodontists making your mail-order clear aligners can’t see and evaluate the health of supporting structures, such as your jawbone and gum tissue. They also can’t see underlying gum disease, which can be exacerbated by any form of orthodontic treatment.

“Better safe than sorry” definitely rings true when talking about the long-term health of your pearly whites: Either your orthodontist will say you’re good to go and send you on your way, or they’ll recommend other treatments to safely, healthfully achieve straight teeth and a proper bite.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.