How Invisalign Works

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Would you like to learn more about how Invisalign works?

Invisalign offers a more aesthetically pleasing option to traditional braces. It’s been proven to correct mild overbite, gapped teeth, crowded teeth, and other moderate teeth-straightening and bite issues.

Invisalign benefits have been well-documented since the early 2000s when patients decided to skip traditional braces for these custom-made clear aligners.

If you’re still undecided if Invisalign’s teeth straightening process is for you, make an informed decision by understanding how Invisalign works.

What is Invisalign Orthodontic Treatment?

To fully understand what Invisalign orthodontic treatment is, and how it works, you need to understand how the teeth move. And that involves a little about teeth and jaw anatomy.

The human contains an important bone called the “alveolar bone”. This bone holds upper and lower teeth firmly in place and provides support from the pressure you exert each time you bite and chew food. The roots of the teeth contain tiny ligaments called the “periodontal ligament”, which is what connects the teeth to the alveolar bone.

The strong attachment of the periodontal ligament to the teeth and bone is important for the proper function of the mouth. This attachment is lost in the oral problem called periodontal disease.

To move the teeth effectively, there should be changes in the bone that surrounds its roots, all while keeping the attachment of the ligament between the roots and the bone. Thus, the objective is to move the teeth within the bone.

For this to happen, some cells need to break down and rebuild the bone. Picture this; a healthy tooth is made up of healthy roots, healthy ligaments, and healthy bones. It is set well set on the jaw. To move a tooth, you need to move the bone out of the way. That requires activation of cells to remove the bone in the direction where you want to tooth to go.

Subsequently, as the tooth moves to its preferred direction and spot, there should be no empty space left behind. This means the healthy bone underneath should not only surround the tooth on all sides, it also needs to activate the cells to build bone on the areas that the tooth moved away from.

These cell activations are what dentists and orthodontists bank on when it comes to correcting malocclusions and straightening the teeth. They put pressure on the teeth to slowly force them to move them in the right direction. The cell activation is simply the body’s natural response to the pressure placed on the teeth. Both the direction and the amount of pressure are crucial in the orthodontic treatment process. Too little pressure and the teeth will not budge from its place. Too much pressure placed at the wrong angle can cause damage to the gums and teeth.

How traditional braces move the teeth

Traditional metal braces use brackets and wires. Dental bonds and glues are applied to the flat surface of the teeth to attach the brackets. Each bracket is equipped with a small channel that fits different types of orthodontic wires. Orthodontists bend, shape, and tighten the wires to apply a certain amount of pressure to specific teeth and areas. Wires pull the brackets, and this pulling pressure causes stimulation and activation for the removal and rebuilding of bone.

The orthodontist changes the wires are changed periodically to ensure a certain pressure is maintained.

How Invisalign moves teeth

The teeth straightening process in Invisalign treatment is quite similar to metal braces – the Invisalign aligners apply pressure to encourage cell stimulation at the roots of the teeth and move the teeth in the right direction. However, the execution and mechanism are quite different.

Rather than attaching to the teeth through dental glue, clear aligners cover the entire row of teeth completely. The Invisalign doctor works with an orthodontic lab technician to get the perfect mold and outline the precise movements of each tooth, from start to finish.

Each movement is predicted by the millimeter, this is why actual aligners are designed in tiny increments. Aligners move the tooth at an average of half a millimeter at a time.

When the removable aligners are worn, their teeth are being pushed to their preferred direction and spot. This pushing activates the bone breakdown at the roots of the teeth, activating the rebuilding process of the cells so the teeth can move and settle into their new spots.

Invisalign Benefits

Convenient and practical

Unlike traditional braces which are fixed on your teeth throughout the process, Invisalign clear aligners are removable. Thus, you can take them out each time you eat or drink. This means no food restrictions throughout the process, and no need to worry about food getting trapped between brackets and wires and damaging the braces.

Also, since you can remove your aligners, it’s a great choice for active individuals who participate in contact sports, if you are attending a special occasion (i.e. weddings), or for a photoshoot.

Virtually invisible

If it’s still not obvious enough, Invisalign is short for invisible aligners. It is by far, the more aesthetically pleasing option than the traditional braces.

Easy care and maintenance – Brushing and flossing with traditional braces can be quite challenging. With removable aligners, on the other hand, good dental hygiene doesn’t have to be tedious. You can remove the aligners and clean them separately, and brush and floss your teeth as you regularly do.

How Does Invisalign Works?

Now that you have a good idea of what goes on inside the mouth anatomically speaking, it’s time to dig deeper into the whole Invisalign process.

Note that the process may differ from one patient to another, as different aspects may require different specifications. Generally, though, the treatment plan for most patients is quite the same.

1. Consultation

As with any orthodontic process, Invisalign consultation is the first step. Patients are invited to the dentist’s or orthodontist’s clinic for face-to-face consultation and assessment of their case.

During your initial consultation, your dentist will discuss the whole process with you; how it works, what to expect, and when to see noticeable results.

A good orthodontist will have no problem discussing the cost of the whole treatment. After which, you are expected to have a good understanding of the entire process.

Photos and X-rays

To get the whole picture of what is going on inside your mouth, especially the positioning of the teeth within the gums, the orthodontist will require dental photographs and dental x-rays. Both will be taken during the initial consultation, once you decide to go ahead with the Invisalign treatment.

The orthodontist will take a series of photos and x-rays of the mouth, teeth, and face from different angles to get a detailed map of the mouth and identify the mechanics of the base for the dental work.

In some cases, the dentist may require a lateral cephalometric x-ray. This type of x-ray provides elaborate images of the relationship between the cheekbone and the jaw of the patient. This is extremely important for planning the teeth alignment, which is the intended goal of the treatment.

Images from photos and x-ray will provide the orthodontist a nice blueprint to work on. The final piece of the process is taking impressions of the teeth to make the molds for the Invisalign aligners.

2. Optional Prep Work

Composite patches

In some cases, patients may be required to have small composite patches attached to each tooth. These patches are made with the same composite material as tooth fillings. They are attached to provide a better grip for the clear aligners on each tooth and move them effectively.

Since each case is different, not all patients are required to have these patches. Also, they will not cause any discomfort or change in the way you bite and chew. More importantly, they can be easily removed at the end of the treatment process.

Interproximal reduction

Another part of the preparatory work is the interproximal reduction. As mentioned in the previous paragraph, each patient is different. Thus, depending on your case, this may or may not be applied to you.

Despite its complex name, the process of interproximal reduction is quite simple – it is done to create more space between teeth. An orthodontist will “sand away” enamel to free up the teeth and allow less restricted movement for the aligners. It is typically used on patients with crowded teeth problems.

3. First Invisalign Fitting

The First Fitting

You will get the first feel of Invisalign aligners at the same time as your preparatory work is done.

The clear aligners are modeled based on your mouth’s impressions. However, since the goal is to move the teeth, the aligners should feel tight when your first put them on.

By this time, your orthodontist will review the fit of your custom-made clear aligners. You may have to try different molds before they are satisfied. Your orthodontist will also ask you how the trays fit and feel in your mouth, whether you can feel the pressure, sense any movements, or feel uncomfortable.

The aligners will definitely feel strange at first; they should feel tight as they are putting certain pressure on your teeth to encourage movement and start the alignment process. You may feel some discomfort, but they shouldn’t be painful.

Make sure you tell your orthodontist if feel any pain or if the fit of the aligners feels distressing in your mouth. However, note that the aligners are specifically designed to move your teeth, thus, they are not particularly comfortable at first. It will, however, feel better over time.

4. First Week of Wearing Invisalign Aligners

Invisalign aligners will feel strange at first, with some level of discomfort and aches. This is completely normal and part of the process of teeth straightening, as your teeth are being moved. Traditional metal braces feel similar in this aspect. The discomfort usually lasts a few days or after the first week of every tray change.

Subsequently, your teeth will feel a little more sensitive than usual. This should subside after a few days. You can, however, use toothpaste specifically designed for sensitive teeth to minimize discomfort. You can ask your orthodontist for recommendations.

You may also notice some changes in the way you speak in the first week or two of wearing your Invisalign aligners. Again this is completely normal as you are still getting used to the feel of wearing the aligners. Plus, though they are thin plastics, aligners will still take up some room in your mouth. This means your tongue may not have the same space to move in as before. This, of course, should disappear after a couple of weeks.

For best results, Invisalign clear aligners must be worn for a minimum of 20 to 22 hours a day.

5. New Aligner Change

Depending on your orthodontist, your aligners will be changed after one or two weeks. If your teeth haven’t moved to the direction and require position, you may be required to wear your current aligner for another week.

Each aligner is designed to move your teeth in small increments. Thus, each change may feel the same as you first wore your first aligner – there will be some discomfort that will last a few days until your teeth move to match the aligner. Subsequently, you will have to visit your orthodontist for regular check-ups throughout the process. This is to ensure your teeth are actually moving and moving at the right place and in the right direction.

Again, if you feel any extra pain or serious distress, don’t hesitate to visit your dentist for a thorough assessment of your teeth and your aligners.

6. Invisalign Process Completion

Final desired position

After you have finished all the trays, your teeth will have straightened out and should be at their final desired positions. The whole treatment process typically lasts around 12 to 18 months. The number of aligners you would have worn throughout the treatment would be somewhere around 20 to 50 trays. This, of course, varies depending on your case.

Subsequently, the results vary depending on the severity of the misalignment. But if you followed your orthodontist’s instructions as prescribed, you are guaranteed to have straighter teeth.

Once you have completed the treatment, it’s time for maintenance, which means wearing retainers. Again, depending on your case, you may have to wear the retainers for 6, 12, or 18 months, or even longer. Your orthodontist will determine that.

Your body changes as you age, and that includes your teeth. Your teeth may shift as you grow older. This can be counteracted by wearing retainers as directed by your orthodontist.

Invisalign Treatment FAQ

Does Invisalign Work?

Absolutely, yes! Invisalign can be just as effective as traditional metal braces when it comes to correcting mild to moderate alignment and malocclusion issues. Yet, less invasive, more comfortable, and by far, more aesthetically pleasing.

How long Does it Take for Invisalign to Work?

Again, it differs from one person to another. It varies based on the type and severity of the malocclusion, how far the teeth should be pushed to their final position, etc. Typically, Invisalign treatment lasts around nine to 12 months. The efficacy also depends on the patient’s level of compliance. The aligners must be worn for around 20 to 22 hours per day. Not wearing the aligners for too long will disrupt the straightening process.

How Painful is Invisalign?

Invisalign will feel tight and you may feel some sort of discomfort or mild pain, but it should not be painful. You will not feel extreme pain from the molding, fitting, up to the wearing stages. The first few wear of the trays will feel uncomfortable and awkward, but that goes away after a couple of days as your teeth adjust to new aligners. You will grow accustomed to the aligners after a week.

Subsequently, attachments on your teeth will not hurt either. There is no need for any type of injection to have them fitted, and they can be removed easily after the treatment.

If you are experiencing some sort of pain and discomfort, you can use a cold compress, ice pack, or a back of peas to numb the area and reduce the swelling. You can also drink cold water or suck on ice cubes.
Your orthodontist may also prescribe some over-the-counter painkillers, such as aspirin or ibuprofen. You can also ask for an oraljel (topical painkiller applied directly to the painful area) from your orthodontist. If you normally feel pain each time you change your aligners, you can take painkillers before changing your aligner for a new one.
Since your mouth is adjusting to the aligners, you may occasionally get mouth sores, as the aligners rub against your gums and/or tongue. You can rinse your mouth with salt water to alleviate the pain.

What Drink and Food Restrictions Should I know?

Unless you are drinking just pure water, you need to remove the aligners each time you eat or drink. Thus, unlike in traditional braces, there are no restrictions when it comes to your diet.

How do I Clean Invisalign aligners?

Cleaning your clear aligners is as easy as taking them off, brushing them with a toothbrush (without toothpaste), and rinsing. You should clean your aligners twice a day, in the morning and at night, before or after you brush your teeth.

Also, the trays should be rinsed thoroughly each time you take them out during the day. This will help keep your aligner fresh and remove bacteria. Also, to avoid discoloration, you need to clean them every meal.

The best way to keep your aligners nice and clean is to soak them in a dental cleaner. Dental cleaners are widely available.

How do I clean my teeth with Invisalign?

Since the aligners are removable, you can clean your teeth by brushing and flossing as you normally would without the Invisalign.

How much do teeth move with Invisalign each week?

Each aligner is designed to move your teeth up to .33mm before the next aligner. Thus, you can expect to swap for a new aligner every week or two.

Can I play sports while wearing my Invisalign?

Invisalign aligners are designed to straighten your teeth; it is not designed to provide cushion and protection in sports scenarios. Thus, when playing sports that require a mouthguard, such as football, martial arts, boxing, grappling sports, or basketball, make sure you take out your aligners and wear a proper mouthguard for the sport. Just remember to put them back on after your activity.

How are Invisaligns removed after the treatment?

Removing your aligners is as easy as taking them off. Unlike in traditional braces, where you need your orthodontist to remove the brackets and archwires, you can take off your clear aligners yourself.

Note that there may be some small resin blobs on your teeth that are used to secure the aligners. Your orthodontist will simply drill these things out and smoothen the surface of your teeth. The final appointment for this can only take 20 minutes or less.

Traditional Metal Braces vs. Invisalign Aligners

Both Invisalign clear aligners and the good old metal braces are intended to correct and improve teeth alignment for a more beautiful smile and overall oral health. While the latter has been around for ages, Invisalign is a new concept specially designed to meet modern needs. Here’s a quick comparison between the two.

  • Appearance – This is the biggest difference between the two, and is usually the reason why people choose Invisalign over traditional metal braces. The clear plastic aligner of Invisalign is virtually undetectable to other people, while braces’ metal wires and elastic bands, of course, are quite obvious. Thus, Invisalign is far more visually appealing.
  • Comfort and Convenience – Straightening your teeth will always feel uncomfortable. Whether it’s with traditional braces or Invisalign, the process of moving the teeth can cause discomfort and some pain. However, Invisalign is far less invasive and tends to be more comfortable than the metal braces. The former applies less pressure than the latter. Also, metal braces have sharp edges that can easily cut the tongue and inner lip. Subsequently, if you play sports, you can simply remove your Invisalign trays. That is not possible with braces.
  • Price – This largely depends on the severity and length it would take to fix the malocclusion. Traditionally, braces are a little cheaper, as they would usually cost around $2,500 to $8,000. Invisalign’s baseline cost is a little more expensive, as it can cost anywhere from $3,500 to $8,000.
  • Length of treatment – Again, this is a case-to-case basis. However, Invisalign treatment tends to be shorter than traditional braces. Invisalign treatment can last anywhere from 6 to 18 months, whereas traditional braces average at 24 months.

Takeaway

Invisalign works, that’s an undeniable fact. But is it for you? The best person to ask that is your orthodontist. Schedule an appointment today and find out if you can be a candidate for the treatment.

Dr Febin Mary George - Editor

With more than 10 years as a dental surgeon, Dr Febin Mary George is passionate about educating consumers around the world to help look after their teeth.

She completed her Bachelor of Surgery at the Century Institute of Dental Science and Research Centre in 2010.

Alongside editing the International Journal of Dental Clinics she has also written for major publications including Thrive Global.