Day & Nighttime Aligners: What Are The Differences?


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About Nighttime Aligners

Recently, I have been approached by patients asking about the difference in daytime versus nighttime aligners and if I had a professional opinion about them. Because nighttime clear aligners are relatively new and widespread information has been limited, I thought it would be a good topic for an educational post.

History of Aligners

Traditional clear aligners have been around for almost 20 years, and with millions of patients treated, there’s a plethora of clinical data to support the treatment. Just recently, there’s been some discussion regarding the use of exclusively “nighttime” aligners, and due to their recent development, there is very little clinical data or patient testimonials to review.

For background, traditional aligners are worn approximately 22 hours a day. They are made out of nearly clear plastic and are worn in the mouth like a tray. They should only be removed to eat, drink, or complete your hygiene routine. In contrast, nighttime aligners are meant to be worn 8 to 11 hours per day in the evening and sleeping hours, depending on the manufacturer.

Doctor Oversight is Essential

As an orthodontist with many years dedicated to the craft of carefully moving teeth and supporting structures, I have always cautioned my patients about do-it-yourself aligner products without regular visits to a trusted and trained orthodontist. Orthodontists can ensure aligners are the right treatment method based on the particular issues a patient needs to address. They closely monitor the patient’s progress and troubleshoot or change the treatment method as needed along the way.

There are several aligner systems that require an orthodontist’s supervision with visits every couple of months, including Spark. These systems deliver great results for my patients at Gire Orthodontics and Ladera Orthodontics. Other mail-order products, like most nighttime aligners, do not involve a doctor to monitor the movement of teeth, their roots, and the supporting structures attached to them. You might see some nighttime aligners that require a remote or telehealth visit, but I don’t believe this is enough. Would you set your own broken leg or arm bone if you fell, or would you see a trained medical specialist?

Background on Nighttime Aligners

There are currently several nearly invisible nighttime aligner products on the market, manufactured by various companies that cut out the role of a trained in-person specialist, the orthodontist. You should note that these are slightly different from each other and claim different treatment times. While all of them require that you wear the nighttime aligners 8 to 11 hours a day, there are other differences between them.

Different Treatment Options

One company utilizes the same nighttime aligner material as its full-time, regular product. So, by wearing the aligners half the time, the treatment time is about twice as long. Instead of wearing each aligner set for one week, they’re worn for two weeks.

Another nearly invisible nighttime aligner brand claims its product is made with a harder material and requires the patient to use a vibrating device that provides micro-pulses for 10 minutes a day. The company claims it can move teeth quicker (4 to 6 months) than competing products. Yet another product appears to be similar to its daytime aligner counterpart and states that the average treatment time is 8 to 12 months, based on the patient wearing it eight hours a day.

An Orthodontist’s Professional Opinion

I do not advocate for products where a doctor’s expertise and follow-through are absent from the treatment process. So, if these nighttime clear aligners interest you, I would strongly encourage you to do your research, speak with your provider, and make an informed decision based on clinical studies and outcomes data.

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Downsides of Nighttime Aligners

Since Invisalign developed the first clear aligner, all orthodontists have followed their treatment plan guidance and required our patients to wear their aligners 22 or more hours a day. There’s a good reason for long-term wear! When a patient removes their aligner for more than just a quick bite or brush, the teeth start to shift back to their original positions. The longer an aligner is out, the more the teeth shift. Not only does this lengthen the treatment duration, but it also puts additional strain on teeth as they continually shift in and out of their intended positions.

Constant shifting with nighttime clear aligners can cause additional discomfort and, because the aligners are only worn at night, could cause some restless or sleepless nights. One last precaution: there is a small risk with any orthodontic procedure of damaging tooth roots. With the added strain of excessive movement, you may have cause for concern about root damage. Root damage is an incredibly important consideration for orthodontic treatment, and it’s something we want to study in the long term before deciding if nighttime aligners are a good treatment option.

Why Clear Aligners?

The objective of clear aligners is to address simple to moderate cases of undesirable spacing, crowding, or malaligned bites. These are intended for patients who want a discreet treatment journey in a fairly short timeframe, and they want it done safely and effectively. Today’s aligners are nearly invisible, especially Spark, with the clearest material on the market. Due to the clarity of the material, there shouldn’t be an issue with wearing them during the day.

For years, dentists and orthodontists have advised their patients to keep aligners in place for as much of the day and night as possible. It’s not to accelerate treatment; it’s to honor the biology and support a safe and healthy adjustment process. Nearly invisible nighttime aligners offer no clear benefit over regular aligners. Instead, they prolong treatment time and increase the risk of root damage.

Making Your Choice

I encourage each patient to do research on their own and speak to an orthodontist about their concerns. The right treatment method for each patient is based on an evaluation of their particular case and needs. If you think nighttime clear aligners may hold some benefit for you over daytime trays, bring your questions to your orthodontic provider for more information!

*The opinions expressed in this article are those of Dr. Robert Gire. Ormco is a medical device manufacturer and does not dispense medical advice. Clinicians should use their own professional judgment in treating their patients.