My fingernails just folded back when trying to get my first tray out. When asked, my orthodontist said there were no tools to help*... I would just, "get better at it." I took my wounded fingers home and made this tool. I hope it makes life easier for someone else.
*Both Outies and Invisalign have tools (available online) that will hook into trays to help you pull them off. This tool will work to push your trays off if they are too tight to hook into.
Step 1: What you need
1- An Oral -B "stimulator". One of those black rubber tipped things the dentist gives you. I found an old stimulator in the bathroom closet. Looking on line just now, they don't seem to have changed. You need the kind that does not include a toothbrush on the other end. (the rubber tip is missing in the picture because I only had one - and now it's a tool)
2- A file
3- About 5 minutes
Step 2: Pull the tip off the plastic handle
Toss the tip in the wastebasket.
This should leave you with a small ball shape attached to the flat side of a small cylinder shape.
Step 3: File the round ball and part of the cylinder into a dull wedge shape
Smooth off any burs or flashing.
Step 4: Try it out - PUSH (don't pull)
Push down with one flat side of the wedge against the open edge of the tray. The tool lets you imitate trying to push the tray off with the back of your fingernail (if that's anatomically possible).
I don't use this tool to hook and pull the trays off. It's intended for trays too tight to hook anything into them. My fingernails are much happier, and it works with my attachments.
After five months of use, I see no wear on my teeth or the tool.