Expanders can be helpful to get over the threshold of having enough space to adequately posture your tongue. I would encourage you to seek out a functional orthodontist in your area willing to work with you in pursuit of this goal. It really isn't as simple as just getting an expander and steadily advancing. The acrylic framework requires adjustments to maintain the fit as you progress. I'm also unsure about how your crowns could impact the process, and would want the advice of a professional on that matter, especially if any of your crowns bridge adjacent teeth. Side effects like gum recession or root resorption might be more of an issue on teeth which have had the enamel reduced for crown preparation, or the marginal line compromised. I don't think the bonded wire retainer on your bottom front teeth would significantly hinder your progress if it is like the picture below.

Yes that is the type of retainer. I am planning on having it removed soon.

I am also concerned about the teeth since they were filed down quite a lot. I am not sure how much the teeth in the front get moved by palate expansion. Maybe someone can educate me. My crowns are on my front 8 teeth, so one pre molar is crowned. No bridge though. I have already ordered the retainer and I'm pretty set on giving it a go, but I'll stop immediately if there are any issues. My main thing is that my palate is so narrow my tongue just can't get up there.

I am always worried about novices who try to use an expander without professional help. There are real risks which might be irreversible. Even if you are resourceful enough to figure out and make the necessary adjustments as you progress or face setbacks, I am especially worried about your crowns. The expander will put considerable force on your crowned canines and first premolars. I just hope they still have enough structural integrity to take that pressure. If you are determined to proceed, I recommend you read TGW's threads about his palate expansion progress and modifications (  /community/community/case-discussions/palate-expansion-update-1/# ) ( /community/community/main-forum/you-can-easily-shave-down-a-palate-expander-to-refit-it-to-your-mouth/# ), and my thread about stepwise removal of the acrylic from behind my anterior teeth (  /community/community/main-forum/expander-adjustment/# ). You could also check out the log of my routine including my expander experience (  /community/community/case-discussions/my-routine/ ). In short, you might consider expanding a couple millimeters until you start to see some reduction in crowding or opening of the contact points between your front teeth and you don't want your canines to move farther, then cut away the acrylic behind the front six teeth. Then you can expand a couple more millimeters until your first premolars have moved as far as you want and cut away the acrylic from behind those teeth as well, leaving only the acrylic in contact with your second premolars and first molars. Here's an image of the acrylic I cut away from my expander in stages:

You'll also have to adjust the labial bow and file down acrylic from the top of the expander to maintain the fit as you advance the screw. Please stop or take a break if you notice anything wrong like gingival recession, mucosal ulcers, pain, etc. I'm not sure what I would do in your situation, but I guess you could consider jumping ahead and remove all of the acrylic from behind your front 8 teeth immediately so that there wouldn't be any pressure on the teeth with crowns. I would just be worried that this would put disproportionate pressure on your back teeth and alveolar ridge, increasing the risk of side effects in that smaller surface area.

Thank you, I really appreciate your help. I'm reading up on everything and your suggestion is pretty much exactly what I intend to do.

Since you can have invisalign treatment while having crowns I think they are strong enough for some amount of movement. I have Emax crowns (read they have about 400-500 MPa) which are possibly stronger than real teeth "Emax and PFM porcelain are a bit weaker (than zirconia) but still stronger than your teeth." Gum recession is a concern through.

My desire to expand my palate and move my jaw up and forward is stronger than my concern about the crowns.

Posted by: iwillgetthere

Thank you, I really appreciate your help. I'm reading up on everything and your suggestion is pretty much exactly what I intend to do.

Since you can have invisalign treatment while having crowns I think they are strong enough for some amount of movement. I have Emax crowns (read they have about 400-500 MPa) which are possibly stronger than real teeth "Emax and PFM porcelain are a bit weaker (than zirconia) but still stronger than your teeth." Gum recession is a concern through.

 

My desire to expand my palate and move my jaw up and forward is stronger than my concern about the crowns.

 

I'm not worried about the crowns; I'm worried about the compromised teeth under the crowns. These are all still vital teeth without root canals, right? The crowns could be replaced if they break or come off, but if the teeth break they might have to be extracted. Then you would be in a position where the dentist would either make a bridge between the two adjacent crowns or place an implant. It sounds like you've made up your mind to try this independently, so just be careful!

They are live teeth yea, no root canals. I plan on taking it slow. You can move crowned teeth with invisalign  but I am not sure how strong the push is with the expander. I have a question though about what you use to cut part of the acrylic expander? A special tool, saw?

Posted by: iwillgetthere

They are live teeth yea, no root canals. I plan on taking it slow. You can move crowned teeth with invisalign  but I am not sure how strong the push is with the expander. I have a question though about what you use to cut part of the acrylic expander? A special tool, saw?

I use a dremel tool with a grinding stone burr, and refine my adjustments using a hand file. 

I'm going to give it a go alone, but I am looking for a right minded dentist in general. In my country there isn't a lot of new thinking it seems.

Posted by: iwillgetthere

I'm going to give it a go alone, but I am looking for a right minded dentist in general. In my country there isn't a lot of new thinking it seems.

Good luck! You sound like you've done the due diligence, so I assume you know how fast to advance. Listen to what your body is telling you, don't ignore warning signs, and set reasonable expectations. Many of the people who attempt this alone only expand a few millimeters before the device is no longer functional because of fit issues. Even if that is all you get, it might be enough to push you over the threshold to be able to correctly posture your tongue.