I forgot to turn the hotplate off and I left a cheap non-stick frying pan on the stove for a few hours. It was set to medium heat. I also left a laguiole inox tablespoon in there with the handle resting against the side of the pan. When I noticed it, I turned off the heat and put the pan on a cold hotplate and let it cool for a few hours.
The spoon's plastic handle looked intact, but then I noticed a deep dent shaped like the edge of a frying pan melted into the spoon's handle. Additionally, on the bottom of the spoon, I saw some black stuff which was either burnt chilli con carne residue or teflon. I noticed it came off when I rubbed it with my thumb under water. Now, the pan looks good as new, and if you ignore the partially melted handle, the spoon looks good too.
However, I am concerned about the teflon, as the heat may have broken it down into something dangerous. Is it safe to eat with the spoon and cook with the pan?