I’ve always loved acronyms. They’re so fun to understand their meaning and learn their history. And who hasn’t had fun trying to guess what the letters stand for when you have no idea?

In orthodontics, we have lots of acronyms for things. And, because humans are creatures of habit, sometimes acronyms keep getting used even though they are not entirely accurate anymore.

So, let’s explore some of the acronyms currently being used to describe appliances orthodontists use to expand the airway and make room for teeth. They all fall under the broad heading of palate expanders. Let’s stay with our theme and call these PE’s.

Where Palate Expanders Began

In the early 1900’s, PE’s came into favor when a group of ENT’s from NYC (see, aren’t acronyms fun!) started encouraging orthodontists to use them on the patients who had chronic breathing problems.

The orthodontists quickly learned that the PE’s worked very well at making room for teeth for them to straighten, and the ENT’s were happy because their airway patients were also getting better.

And because no one wants to keep a PE in their mouth very long, and because the orthodontist wanted to get busy straightening the teeth, they started turning the PE’s multiple times each day so they could be finished with them sooner.

So, they started calling them Rapid Palatal Expanders or RPE’s.

RPE: The Rapid Palatal Expander

The RPE acronym has been around for a long, long time, and in orthodontic circles everyone knows what they are. It’s an appliance we install for a specific purpose, and they work like magic—no pain, just expansion.

Interestingly, in the 1990’s, after many years of clinical research, orthodontists learned that you could achieve the same effects (palate expansion to make room for teeth and airway improvement) even if you turned the RPE’s slowly.

So, instead of turning the device 2, 3 or 4 times per day, we’d ask our patients to turn them 2, 3 or 4 times per week.

But undeterred, we kept calling the appliance an RPE. We didn’t rename it SPE (Slow Palate Expander).

Any patient who was still growing could be a candidate for an RPE. Once growth ceased, the only option for bony expansion was surgery.

MARPE: Palatal Expansion With Mini-Implants

Then, in the new century, orthodontists combined two techniques to expand palates which has drastically increased the number of patients who can benefit from them.

We now use mini-implants secured to the palatal bone through the RPE so patients who are no longer growing can also get the benefits of PE. Adults can now get expanded and expect the same sort of results we get for kids.

These new devices have been named Mini-implant Assisted Rapid Palatal Expanders or MARPE’s. (I know, I know—it should be MIARPE but who wants to say that?)

And of course, we figured they would only work if they were turned rapidly. So, we stayed with the R (for rapid, 2-3 times per day turning) in the acronym.

Does a MARPE Have to Be Rapid?

After 10-20 years of trial and error, we have learned that turning a MARPE slowly will work just as well in expanding a palate and avoid some of the other negative side effects like getting a giant space between your two front teeth, breaking bones, tearing skin—all the fun stuff.

But guess what, the MARPE acronym stayed with us.

You tell some orthodontist smarty pants that you want to get a MARPE and they know exactly what you’re talking about. The next question would be: what is your turning protocol?

Same device, different turning protocol—just like the RPE’s from the early 1900’s.

So, What Is a MASPE?

The marketing people took over.

“Hey, we can differentiate ourselves by selling this new gizmo that works just as well with fewer side effects by renaming it the MASPE.”

It’s the new and improved Mini-implant Assisted SLOW Palatal Expander.

“Let us expand your palate and you won’t get a space between your front teeth the size of your finger.”

Hmm, same device, different turning protocol.

It’s a Mini-implant Assisted Palatal Expander? A MAPE?

Nope. No one wants to say they have a MAPE in their mouth when a MASPE sounds so much cooler, right?

MASPE vs. MARPE: Same Idea, Different Acronym?

MASPE, MARPE, RPE, SPE…Can’t we all just get along?