This is Chapter 7.3 of the JawHacks ebook. See the full Table of Contents here.
Intro
In this chapter, we will discuss two situations in which MARPE ought to be considered in addition to jaw surgery.
The two scenarios are:
maximizing all potential nasal breathing improvement
decompensating crowded teeth in order to maximize skeletal advancement during jaw surgery
In such cases, it is always better to do MARPE first, then jaw surgery second, as doing MARPE after jaw surgery is risky and unpredictable.
We will also discuss one scenario in which it may be better to skip MARPE entirely and seek expansion instead via a segmental Lefort.
1. MARPE Before Jaw Surgery for Nasal Breathing Maximalism
What MARPE and Jaw Surgery Can Both Do for the Nose
The roof of the mouth and the floor of the nose share the same structural bone, namely the hard palate.

It is analogous to floors in a building, where the ceiling of one room shares a frame with the floor of the room above it.
MARPE and jaw surgery can both widen the palate, and in doing so, they widen the floor of the nose which increases nasal volume and decompresses the nasal airway.
MARPE does this via distraction osteogenesis - gradually turning an appliance that spreads the palate apart.
Maxillofacial surgeons do this via a segmental Lefort operation, in which the maxilla is cut into multiple segments and widened and advanced simultaneously, during a single procedure.

MARPE and jaw surgery both create more real estate at the roof of the mouth and floor of the nose, but there are important differences between them.
What Only MARPE Can Do for the Nose - Vertical Expansion
There is not much that MARPE can do that jaw surgery can’t, but vertically expanding the nasal airway is one of them.
The image below, courtesy of Shuikai, illustrates what we mean by “vertically expanding” the nasal airway. The image shows a superimposition of a very modest EASE (a kind of MARPE) expansion of about 2mm.
You can see a midline fracture, as well as a diastema between the central incisors, which are indicators that the palate has split and is widening.
But pay special attention to the piriform rim higher up, above the two green lines. The expansion is occurring all the way up the nose, to the base of the eyes. This is remarkable.
So if the nose is thought to be a triangular prism, then the expansion is occurring not just at the base of it, but all the way up to the vertex.
This is not the case with nasal expansion that occurs with a Lefort 1 jaw surgery, as the Lefort cut occurs beneath the cheekbones and cuts off the nasal expansion from going above that point.
What Only Jaw Surgery Can Do for the Nose
Now, it’s also true that jaw surgery can improve nasal breathing in ways that MARPE cannot.