Even the dull blades will cause major damage just in your mouth let alone if you were to partially swallow one or all. I stopped doing this and the needles long ago because of the danger factor and having cuts in my mouth or on my tongue. . . but I stopped doing a lot of the more dangerous stuff with age.
PLEASE. . . don't refer to small tricks as "Illusions". . . I know it's a linguistics thing but when you say "Illusion" and you're talking magic, the majority of old timers think of Grand Illusion -- levitations (not standing on your tippy toes but actual floatings & suspensions), Cutting into poeple into pieces, etc.