The Invisalign system is one of the most modern ones used in orthodontics, redefining all this treatment. Now, you can forget about the normal braces, the ones made of ceramics or even placed in the “back” side of the teeth. Invisalign straightens your teeth by using some plastic “mouthguard” like trays, you change every 2 weeks, for as long as needed till the end.
If you want more details about Invisalign, please read our presentation article. Now, we’ll try to focus on “how it’s made”.
Any orthodontic treatment starts with the initial consultation and this doesn’t break the rule. Your orthodontist will check you with great care and, should you “qualify” for Invisalign, you’ll be ready to undergo the first step to the trays: your molds.
For the Invisalign specialists to really be able to create your UNIQUE trays, they will need perfect impressions. So, don’t be scared if your orthodontist is that determined to have them perfect. They are needed this way since your entire treatment for all these months will depend on them. At Align Technologies your impressions, the information about the course of treatment and all other initial materials, will be taken by other specialists in orthodontics.
They will make a positive out of your dental impressions; the plaster molds helping them see your teeth in their normal form. Because your orthodontist was so careful with those impressions, now, the Align Technologies specialists almost have your “teeth” there, and you won’t have to travel thousands of miles just so they can also do your consultation.
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 like 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 overnight, so all these stages are just the normal tooth movement created with each aligner till the teeth are straight and the bite corrected.
The quality check process is next, so that all the process, the teeth movement, prescribed treatment, etc. are correct.
The orthodontist who takes care personally of the patient is the one to decide if the treatment is a “go-go”, together with the patient him/herself. This application form is called “clincheck”
After all the treatment was checked and approved the aligners will be created. A series of models are created of photosensitive thermoplastic, each of them will then be turned into an aligner. The thermoplastic 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.
The aligners are polished and disinfected in a series of cleaning tanks, each set being then packaged, labeled and shipped to the prescribing orthodontist.
And, if you want to see the film, here are all these words in action.