Will Invisalign be able to revolutionise jaw expansion?

Jaw expansion is a relatively common treatment for growing patients. Many children have a narrow jaw for various reasons, whether due to habits, a respiratory problem, genetics or inadequate function. This jaw deficiency can be treated with different appliances: Hawley plates, disjunctors, Planas tracks... or the problem can even be compensated for by expansion with brackets or aligners. Each of these techniques has its pros and cons, although we will postpone their analysis for another article.

Regardless of the appliance we use, if we want our treatment to transmit an effective orthopaedic force, capable of modifying the anatomy of the maxillary bone, we must be able to generate forces in excess of 400-500 g. Here we could open the debate on what type of expansion is best for patients:

• If we follow Planas' theory, it is not necessary to separate the suture with a disjunctor, but by placing plates with which to gradually "push" the process inside the alveolar bone and stimulating the development of the bone with masticatory function and occlusal rubbing, we can resolve the maxillary transversal deficit, achieving maxillary expansions of 6, 7 or 8 mm. Here, the appliance is not applying orthopaedic force, but we are using the forces applied by the patient on the appliance, which is the transmitter of the stimulus.

• If we opt for the fast track, with a tooth-supported or palate-anchored micro-screw device we can achieve the same amount of expansion in a matter of days, with the requirement to keep the appliance in the mouth for a minimum of 5-6 months for new bone to form in the suture we have opened.

Different treatments, different philosophies, more or less similar results. In the first case, we could consider the treatment more "physiological" and less aggressive than the circuit breaker. If we were to survey a number of orthodontists, the percentage of doctors who use disjunctors would surely exceed those who use Planas plates to achieve maxillary expansion. But why does this happen? BLOG 23

It should be remembered that despite their proven efficacy after decades of use, disjunctors are not free of risks: decementation, ulcers, excessive overturning of the supporting teeth, recession, dehiscence, etc.

And this is where Align Technology comes in. This company, despite its size, continues to grow and develop, making a strong commitment to innovation in the field of digital orthodontics. Aware of the high percentage of growing patients who need jaw expansion treatment, they have managed to design a device with which to treat this problem. And no, this time they are not aligners.LOG 23

For the first time, Align is stepping out of its usual production line and has decided to create a new device made by 3D printing. This device (or rather series of devices) is made of a rigid material adapted to the anatomy of the posterior teeth and the surface of the palate. It works very simply: Day after day, the patient gradually puts on a new appliance. With each change, there is an activation of 0.25 mm of expansion. It sounds simple, but the challenge of achieving skeletal expansion with a removable appliance is not.

This device, unlike a circuit breaker, has no emergencies: It does not rub, does not come apart, does not need to be turned with a key... Moreover, it combines support on the palate with dental support to transmit the expansion force to the dentoalveolar processes and push them towards the vestibular region, thus expanding the maxilla. There is little more we can report to date. We know that Dr. Sandra Tai is testing it in Canada and is achieving satisfactory results. For the moment, in Europe we have to wait at least until next year to be able to use it.

A priori, although it does not follow the same philosophy as the Planas plates, its design is promising. As with any new device, my scepticism leads me to the desire to try it out and analyse its effects personally. If this jaw expander works, it will be an incredible breakthrough in the field of orthopaedics, greatly improving the treatment experience for growing patients.

Larena J. RNO 2 Appliance: Flat Plates with run-in or indirect tracks. 2014
Align Technology Website/Investors. Align Technology Introduces the Invisalign Palatal Expander System to Address Skeletal Expansion in Growing Patients, Including Teenage Patients Which Represent the Majority of Orthodontic Case Starts Globally. 2023.