There are a variety of MARPE designs. Some are better suited for certain cases than the MSE. The appliance you referenced is used with the EASE procedure after surgical release of the midpalatal and pterygomaxillary sutures. It might not be as suitable for nonsurgical expansion in adults without the direct forces on either side of the midpalatal suture created by the bicortical MSE TADs. Dr. Marianna Evans discusses this appliance at around the 22:16 mark in this video ( https://www.pathlms.com/pcso/events/1648/video_presentations/143837 ). She says "When you look at the literature, the use of implants for expansion did not really start by orthodontists, did not start at UCLA [i.e. MSE]. They started by oral surgeons 20 years ago, 1999! One of the first papers came out on bone anchored, surgically assisted, skeletal expansion, with this device. So today, this device is still present on the market and has been significantly improved by KLS Martin and is being used by some oral surgeons. This device does not require orthodontist to place the expander prior to expansion, and it will require incisions. So you have to make incisions to [unintelligible] the expander into the bone. So if you have a thin buccal plate, and thin palatal plate, it's a problem. So you have to place them very appically, and it also would be a problem because you have to make incisions. Once you start turning that expander you can create inflammation and ulceration in the gingiva. So they are not going to be a standard of care for an average case, but there are places, indications, to use these devices because they have different sizes."

Yeah the ulceration sounds like it could become a real issue. Seems a lot simple than an MSE for DIY job though.

Posted by: @sb4

Yeah the ulceration sounds like it could become a real issue. Seems a lot simple than an MSE for DIY job though.

I think this takes even more expertise to install because it requires cutting open the gingiva to plant the feet into the bone. Dr. Evans says in that video that it's used by oral surgeons rather than orthodontists for this reason. It also seems like it would occupy even more of the tongue space than the MSE, preventing good oral posture during the course of treatment.

Posted by: @apollo

Posted by: @sinned

Can someone elaborate on this, it sort of makes sense because the MSE is screwed right next to the suture and internal structures of the maxilla. I think the best structure to transfer the force is the alveolar bone that holds the teeth because it can take more force than the teeth themselves. You'll still get the effect that's described but without the downsides of using the teeth as an anchor. 

There are MARPE appliances designed with TADs anchored into the alveolar ridge, or acrylic pads that transfer some of the force to the alveolar ridge. They might be more appropriate in some cases. I think the MSE design with the TADs along the suture and into the nasal cavity is designed to get more parallel expansion and better opening of the nasal passages. Placing the TADs farther from the suture might allow more room for bending/remodeling of the bone to occur rather than splitting the suture. TADs won't get bicortical engagement on the alveolar ridge so this placement might be less stable. The MSE arms are designed to be offset from the alveolar ridge to avoid impinging the tissue. Anyway, there could be cases where the type of design you're describing would be better, but I'm not sure when it would be indicated. For example the EASE procedure uses an expander anchored in the alveolar ridge, but in that case the suture is already surgically separated.