I would suggest getting rid of it, if it got that hot, the integrity of the metal is now in question. You dont know the reason why this happened and it could happen again. Some of the issues with these are due to poor engineering and manufacturing. IF you want to attempt to figure it out, you need to get a meter that reads resistance and check the heating element resistance and divide the voltage by that number to get the amperage, then you can look and see what the wire rating is for the ampacity and check to see if it is in specification.
