How does Invisalign work to move teeth?

Invisalign treatment is effective because it takes advantage of the physiological processes that are currently taking place in your mouth to move specific teeth to their correct position. 

The forces of compression and tension are softly captured by Invisalign aligners, which then control them to gradually realign your teeth. 

IInvisalign uses the SmartForce concept that uses attachments to enhance tooth movement during treatment. These attachments apply specific forces to achieve different types of tooth movements such as extrusion, rotation, torque control, and intrusion.

For the duration of your personalized Invisalign treatment, you will receive a new set of aligners every two weeks, sometimes with variations in the positions of attachments to deliver the desired effect. Your teeth will move with each new pair of clear aligners for about 1/10mm within the first three days of wearing them, and between 0.25-0.33mm within the 2 weeks of wearing them.

Although it’s remarkable, it’s important to note that in most circumstances, the number just shows the mobility of your periodontal ligament. It does not take bone mobility into account. Patients normally need to wear each set of Invisalign aligners for two weeks because it can take that long for your ligament’s fibers to apply enough cementum to join to your bone in a new location.

How does Invisalign work to move teeth

How does invisalign move teeth with SmartForce?

SmartForce is a concept introduced in 2009 to improve the movement of teeth during Invisalign treatment. It involves the use of attachments, which are small tooth-colored buttons that are bonded to the teeth and help facilitate specific movements. 

SmartForce buttons have a beveled surface on the biting surface, which allows for better delivery of certain forces.

Attachments for Different Tooth Movements

Attachments are designed to apply specific forces to achieve different types of tooth movements. Depending on the treatment plan, different types of attachments can be used for extrusion (moving a tooth out of the gum), rotation, torque (correcting the angle of a tooth), and intrusion (moving a tooth into the gum). The type of attachment used and the direction of force applied depend on the desired tooth movement.

Importance of Moment to Force Ratio

In mechanics, a couple refers to two parallel forces that have equal magnitude but opposite direction. When attachments are used, they generate couples that create moments (forces that cause rotation) to move teeth in a desired direction. 

The moment to force ratio (M:F) is an important consideration, as it determines the type of tooth movement that can be achieved. 

  • Tipping movements require a low M:F ratio
  • Translation movements require a medium ratio, and 
  • Root torque movements require a high ratio. 

It’s crucial to balance the forces and moments to achieve the desired tooth movement while minimizing the impact on the anchorage (stability) of other teeth.

Types of Attachments

Attachments can be likened to handles used to move a sliding door. Prior to SmartForce, attachments were primarily ellipsoid, rectangular, or rectangular beveled in shape. While these attachments provided some benefits, they were limited in their ability to facilitate comprehensive orthodontic corrections. The G3 concept introduced power ridges built into the aligners and direction-oriented active surfaces on optimized attachments, allowing for more complex movements like rotations and torque control.

SmartTrack and Tooth Movement

With the improved elasticity of SmartTrack material, a force applied to an active surface can effectively move a tooth in any direction. However, when planning tooth movements, especially when aiming for bodily (translation) movement, the anchorage must be carefully considered. Without sufficient moments, there is a tendency for teeth to tip rather than move as a whole unit. Balancing the forces and moments is essential to achieve the desired tooth movement.

How well does Invisalign work?

Invisalign treatment utilizes nearly invisible aligners to gradually move teeth into proper position. Similar to conventional braces, the goal is to achieve long-term tooth alignment. The periodontal ligament, composed of collagen fibers, serves as an anchor that connects teeth to the jawbone.

Tension and compression forces applied during biting and chewing stimulate reactions in the ligament, cementum, and bone.

By leveraging these natural processes, Invisalign aligners manipulate tension and compression forces to reposition teeth slowly and gently. The aligners facilitate the resorption of bone and cementum, followed by the deposition of new bone. 

Patients typically receive a new set of aligners every two weeks, with each set capable of moving the periodontal ligament by 0.25mm within the initial three days.

For the repositioning to last, bone must also move and hold the teeth in their new position. Wearing the aligners for the recommended duration is crucial to allow the ligament’s fibers to attach to the bone adequately.

Consistent aligner wear, typically 20-22 hours per day, minimizes the risk of relapse or reverse movement. Aligners should only be removed for essential activities, ensuring optimal treatment effectiveness and the realization of a beautiful smile.

How does invisalign move teeth?

Understanding the Biology Basics

  • The periodontal ligament plays a crucial role in connecting teeth to the jawbone. It is a specialized connective tissue that surrounds the tooth root and attaches it to the alveolar bone. This ligament acts as a shock absorber during chewing, providing stability and flexibility to the tooth.
  • Collagen fibers are the main structural component of the periodontal ligament. These fibers are responsible for anchoring the tooth to the surrounding bone. They extend from the cementum, a thin layer of hard tissue that covers the tooth root, to the alveolar bone.

The periodontal ligament creates a sling-like structure around the tooth, allowing for limited movement. This arrangement enables the teeth to withstand the forces exerted during biting and chewing while maintaining their position. The fibers of the ligament provide a flexible support system that allows teeth to adapt to functional and environmental factors.

Constant Changes in Your Mouth

Teeth are not static structures but undergo constant changes due to the dynamic interactions of the periodontal ligament, cementum, and jawbone. These components of the tooth-supporting structures respond to various stimuli, including mechanical forces and biochemical signaling.

When you bite down or apply pressure to your teeth, tension and compression forces are generated within the periodontal ligament. Tension forces occur on the side of the tooth opposite to the applied force, while compression forces develop on the side where the force is applied. These forces stimulate cellular activities within the ligament and underlying bone.

To maintain balance and tooth position, the body regulates a delicate balance between bone resorption and deposition. When tension forces are applied, bone resorption occurs on the compression side, allowing the tooth to move. Simultaneously, bone deposition takes place on the tension side, stabilizing the tooth in its new position. This continuous remodeling process is regulated by various cells and signaling molecules.

Leveraging Natural Processes for Tooth Relocation

Step 1: Invisalign Aligners Capture Tension and Compression Forces

Invisalign aligners utilize the natural tension and compression forces that occur during biting and chewing. The custom-made aligners apply gentle pressure to specific teeth, capturing these forces and directing them to move the teeth gradually. By strategically planning the sequence of aligners, orthodontists can achieve precise tooth movements based on the patient’s treatment plan.

Step 2: Resorption of Bone and Cementum Preceding Tooth Movement

Before the actual tooth movement occurs, there is a process of bone and cementum resorption. As the aligners exert controlled forces on the teeth, bone cells called osteoclasts are activated, leading to the breakdown and resorption of the bone and cementum in the path of tooth movement. This resorption creates space for the tooth to migrate within the alveolar bone.

Step 3: New Bone Deposition Following Tooth Movement

After the tooth has moved to its desired position, a process of new bone deposition takes place. Osteoblasts, specialized bone-forming cells, are stimulated to lay down new bone in the areas where resorption occurred. This new bone supports the tooth in its new position and provides long-term stability.

Role of Invisalign Aligners in Gradual Tooth Movement

New Sets of Aligners Every Two Weeks

Invisalign treatment involves a series of custom-made aligners that are changed approximately every two weeks. Each set of aligners is specifically designed to apply incremental and controlled forces to gradually move the teeth according to the treatment plan. The progression from one aligner to the next allows for step-by-step tooth movement.

Initial Periodontal Ligament Movement Within the First Three Days of Wearing Each Aligner Set

When a new set of aligners is worn, the initial response occurs within the periodontal ligament. In the first three days of wearing each aligner set, the periodontal ligament fibers begin to adjust and adapt to the new forces exerted by the aligners. This early movement sets the foundation for further tooth repositioning throughout the aligner treatment process.

Bone Movement and the Importance of Wearing Aligners for Two Weeks to Maintain Tooth Position

While the initial response is observed within the periodontal ligament, bone movement is also a crucial aspect of Invisalign treatment. The aligners create controlled forces that lead to bone remodeling, allowing the teeth to gradually shift within the jawbone. Wearing each set of aligners for the recommended two-week period ensures sufficient time for the bone to adapt and support the teeth in their new positions.

Importance of Compliance for Successful Treatment

Compliance with wearing Invisalign aligners as prescribed by your orthodontist or dentist is essential for successful treatment outcomes. Inadequate aligner wear increases the risk of relapse or reverse movement, where the teeth may shift back to their original positions. Consistent and diligent aligner wear helps maintain the progress achieved and minimizes the need for additional treatment or prolonged wearing of aligners.

To ensure optimal results, it is recommended to wear Invisalign aligners for 20 to 22 hours each day. This extended wear time allows for consistent and uninterrupted application of forces on the teeth, promoting effective tooth movement. Adhering to the prescribed duration is crucial for achieving the desired treatment goals within the estimated timeline.

While wearing aligners for the majority of the day is important, they should be removed only during essential activities such as eating, brushing, flossing, and cleaning the aligners themselves. This ensures proper oral hygiene maintenance and prevents food debris from being trapped between the aligners and teeth. Maintaining good oral health throughout the treatment process contributes to overall treatment success.

Does Invisalign move your jaw?

Because your bone is what will hold your teeth in their new place, your jaw bone must shift for the repositioning of your teeth to last. 

Your teeth are moving, even though you might not be able to notice it. Your periodontal ligament, cementum, and jawbone move as a result of shifting oral stresses. When you bite down, tension and compression are created, which are then sent to your ligament by the many protein fibers in that ligament. 

Cementum deposits form in the bone as a result of tension. Contrarily, compression is the breakdown or resorption of bone and cement. These antagonistic events take place to maintain equilibrium and keep your teeth in place.

Knowing some biology fundamentals can be very helpful in understanding how Invisalign aligners realign teeth. Teeth and your jawbone are joined by a periodontal ligament. A collection of fibers that contain the protein collagen make up this ligament. The ligament’s fibers act as an anchor to hold your teeth firmly against the underlying bone.

By depositing what is aptly referred to as cementum into live cells on one side of the bone, the collagen fibers adhere to root surfaces. The fibers of your periodontal ligament that are on the opposing side affix to your jawbone. 

Your ligament’s fibers essentially form a sling over your teeth, holding them in position while allowing for some movement as they adapt to the forces of biting.

Is Invisalign Right for Me?

The quality or effectiveness of Invisalign depends on a number of factors. According to professional dentists, these factors may include the skill of the specialist, meticulous case selection guidelines, and seriousness of the case.

Generally, if there’s a particular case where there are doubts about how well Invisalign will work, then it’s safer to opt for the method with greater chances of success, rather than simply choosing an approach based on merely cosmetic desires.

For the duration of your personalized Invisalign treatment, you will typically receive a new set of aligners every two weeks. Your teeth can move with each new pair of clear braces you get. 

Are braces or invisalign more effective?

The Invisalign system has proven to be effective in both clinical research and in practices nationwide. Invisalign is effective because it takes advantage of the physiological processes that are currently taking place in your mouth.

The aligners used during treatment are frequently referred to as Invisalign braces or invisible braces by persons who are familiar with the Invisalign system. This is because the aligners used for Invisalign are practically undetectable. In fact, there is a compelling argument that Invisalign aligners are virtually unnoticeable when compared to traditional braces.

Because Invisalign aligners move teeth in a manner similar to that of traditional braces, calling them braces is also reasonable. Both conventional braces and Invisalign treatment aim to gradually shift teeth into the right position—not instantly. While this is the case, using Invisalign and wearing your aligners for the prescribed 22 hours per day can occasionally hasten the process. 

On the other hand, those who choose traditional braces are unable to hasten their results. This makes Invisalign somewhat more effective than braces.

Benefits of Invisalign for adults

Here are a few other reasons why Invisalign is arguably more effective than braces:

  • It is removable – This allows you to brush and floss normally, helping to prevent tooth decay and periodontal disease.
  • Improved gum health – Studies show that the health of gum tissue tends to improve for the duration you’ll be wearing aligners
  • Enjoy your favorite foods/drinks – Since you can remove them, you don’t have to necessarily forego some types of foods or drinks
  • Cleaning are easier and faster compared to conventional orthodontics – Reducing the risk for plaque retention, tooth decay, and gum disease
  • Improved speech and chewing – Poorly positioned teeth may lead to eating and speaking problems that can be corrected by adjusting your bite.
  • Lower risk of abnormal wear and dental trauma – Properly aligned teeth don’t cause excessive pressure on the supporting bone and jaw joints
  • Dazzling smiles – You will feel less conscious about your mouth, increasing your confidence

Schedule your consultation with an orthodontist

It can be difficult to choose between traditional braces and Invisalign because each has advantages and disadvantages. The two orthodontic treatments vary in regard to cost, aesthetics, and treatment time. Usually, the most important factors to consider can be those over which you have no control, such as the degree of your overbite and whether you have any dental problems that would require treatment. So make sure to discuss with your orthodontist whether Invisalign is the right treatment for your case.


  • Editorial team

    A team comprising oral health care professionals, researchers, and professional Writers, striving to impart you with the knowledge to improve your oral health, and that of your loved ones. 

  • Lilly

    Lilly, aka, Liza Lee, is a passionate community oral health officer and our lead writer. She's not only well-versed in performing a multitude of dental procedures, including preventive, restorative, and cosmetic, but also an avid writer. Driven by the significant oral health burden all around her, Lilly strives to build capacity and promote oral health. She envisions making a lasting impact by advancing research, prevention, and promotion efforts to alleviate oral health disparities. Please share your views and opinions on my posts.

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