Orthodontic Expander Key Holder

thingiverse

My child recently had an expander placed in her too-small mouth, but we were only provided some large metal keys to turn the jack screw. My large fingers not having space to turn the key led to gagging and fears that I could easily drop the key down her throat. We needed a better solution. After seeing a commercial device on Youtube, I looked at purchasing one, but they were only sold in bulk packs and had longish lead times. I found a printable version on Thingiverse, but it uses a snap-fit design and 3 of my 4 attempts to make it broke while snapping it together. I was afraid it could still easily break while in-use, leading to a potentially dangerous situation. This design is glued together to ensure nothing can break apart. The two small circles form the pivot for the key. These pieces are glued together with just a drop of glue (I used super glue) and the design limits the possibility of glue from interfering with the smooth motion. The metal pin ‘key’ is then glued in the 1.5mm hole as well. We’ve used this version for a week (10 turns of the initial 30 needed) and it’s infinitely better than manual key alone — it has made what was a very stressful task for my daughter and I into an easy routine that will ensure we make all the necessary turns of the expander. This device is vastly smaller than my fingers, so she’s not gagged while turning the screw and I have no concerns about it accidentally falling apart.