What are Invisalign braces?

Gregory J. Jorgensen, DMD
Orthodontics & Dentofacial Orthopedics

Invisalign is the trade name of a tooth movement system that uses custom-made plastic aligners to move the teeth. Your orthodontist aligns a digital representation of your teeth on a computer screen dictating where and how your teeth will move to reach their desired positions. Computer software then uses complex formulas (algorithms) to create a series of plastic shells that each moves the teeth just a little at a time. These shells or aligners are worn fulltime for two weeks each until the teeth are straight. The advantages of the Invisalign system are that it is virtually invisible and that the aligners can be removed for eating and brushing. The downside is that since they are removable, the success of the system is 100% dependent upon patient cooperation. If a patient does not wear the aligners, the teeth will not get straight. Just like braces, the teeth will get sore and retainers will be required at the end of treatment.

Invisalign braces are quite different than traditional metal braces. Instead of having brackets and wires attached to your teeth, Invisalign braces are actually a series of “aligners” or trays, similar to what you might have seen with some teeth whitening products. You can take these transparent trays off when you eat and drink, and when you brush your teeth. But while you’re wearing the Invisalign braces the rest of the day and night, they still move your teeth a little at a time, just like regular braces.
Todd A. Welch, DMD
Invisalign braces are the most modern technology used in orthodontics, redefining orthodontic treatment.  Invisalign straightens your teeth by using some plastic “mouthguard” like trays, you change every 2 weeks, for as long as needed till the end.
The plaster models are checked again and cleaned. Any residue or imperfection is manually checked and solved, so that the plaster can enter the other stage: 3D processing. State of the art scanners are able to create a three dimensional version of these plasters, and these can now be processed on the computer. A barrier coating is applied to protect it from the possible damage it can take on the next stage. Once sealed, the models get placed into a chase, then in a mixture of urethane resin and hardener. They spend some hours in a vacuum pressure chamber the resin hardens and makes them look as blocks. Each tray gets into a destructive scanning machine. This removes paper thin slices 3000 of an inch, while a digital camera takes two dimensional images of each of these slices. The computer gathers more than 300 such images to create the 3D model.

These materials get sent to the technicians, who check once again if all is correct, the teeth and also the bite as the patient has it. The graphic designers will use a proprietary 3D application to cut each tooth and save it as a separate geometrical unit. The teeth are now separated and re-grouped on each arch in the position they will have once the treatment is complete. From the initial stage to the final result, there are many intermediate stages that make up the entire treatment. These are carefully considered since the treatment is different for each patient and the entire orthodontic process needs time. As in traditional braces case, we cannot have straight teeth over night, so all these stages are just the normal tooth movement created with each aligner till the teeth are straight and the bite corrected.

A series of models are created of photo sensitive thermo plastic, each of them will then be turned into an aligner. The thermo plastic sheet is pressed over each model by the use of heat. Trimming comes next so that the aligners come half a millimeter under the gum line, reducing the chances of sores and making the removal easier for the patient.
Dante A. Gonzales, DMD
Orthodontics & Dentofacial Orthopedics
Invisalign is a brand name of an orthodontic appliance that is used to align the teeth and bite. The Invisalign appliance is a series of clear plastic trays that are custom made for each patient. Using a 3-D computer image created from an impression of the patients teeth, the dentist, or orthodontist, dictates through a computer software program how and where the teeth should move. The trays are then manufactured according to the movements in the software. Each tray that the patient wears will move the teeth a very small amount until all of the teeth are in their desired final position.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.