This is Chapter 5.3 of the JawHacks ebook. See the full Table of Contents here.
1. MSE Type 2 (Maxillary Skeletal Expander)
MSE was “the first in and best dressed” to the MARPE scene back in 2018/2019. This is the appliance I did, in summer of 2019. It was invented by Dr. Won Moon and paved the way for all other appliances we will discuss.
Rigidity - Relatively weak and flimsy. Tends to bend and distort in the presence of large resistance forces such as those in adult males.
TADs - Relatively poor anchorage due to lack of custom TAD placement, posterior bias (bone is thinner in the back of palate), wide TAD lumens, use of only 4 TADs in the stock appliance, although it could be fabricated with 2 additional TADs.
Location - Generally placed posteriorly in the palate, which means that when MSE actually worked, it often resulted in a nice, posterior nasal expansion. Posterior placement has a dark side, though, which is that palatal bone is thinner there resulting in greater chance of screw drag through the bone, and resulting failure to split or a disorientation of the appliance which could lead to asymmetry.
Arms - Its weakness causes it to depend on arms being added to bolster stability and anchorage in older patients.
Conclusion - MSE
Deserves respect for paving the way, but now MSE is reserved for kids and teenagers. Its flimsiness and lack of customizability results in a high percentage of failure to split as well as poor dimensional stability at later stages of expansion. Starting in 2020 and 2021, we started seeing providers use tandem MSE (2 MSE’s at the same time) in order to compensate for its weakness. This is very telling.
2. Partner’s Dental Studio Custom MARPE
This variation on MARPE was championed by master MARPE provider Dr. Ilya Lipkin beginning in 2021. It was the first major paradigm shift in the delivery of nasomaxillary expanders. The great innovation here was the superimposition of surface data of the palate (from an Itero scanner) with CBCT radiograph data.