Teeth - Fillings?

why is it when you bite a bit of foil, it hurts like hell..





i always thought it was because, the fillings are metal.. this sounds stupid, but i thought that when the material hit your filling, it was positive sides onto negative.. and it reacted and hurt..





people settle this for me

Teeth - Fillings?
http://www.theanswerbank.co.uk/Article23...





sorry had to get that from browser as i also wondered about it many years ago
Reply:thanks drumming..pleased it helped you and it also answered the question i have always wondered about Report It

Reply:i'm 34 and have no fillings but this sounds awful and now I dread my first filling, which I have an appointment for in two weeks.
Reply:If you know it hurts why do you do it. You wouldn't then need to ask this question
Reply:Something to do with the foil reacting with mercury. I remember with the old kit-kat wrappers if you ate the foil it would hurt like f**k!
Reply:what a good question..cud be an electrical charge like a magnetic flux
Reply:instead of having dentine %26amp; enamel between the nerve %26amp; the outside of your teeth/tooth,


you now have a filling, not sure what metal they use as it varies from country to country %26amp; dentist to dentist.


the metal hits the metal %26amp; makes your nerve sing.


i get the same thing when i eat sweet stuff, it makes my nerve tingle %26amp; is why i avoid sugary stuff.


hope that helps coz that's the best i can come up with.
Reply:Putting foil on your fillings creates a small battery (a geek might call it an "electrochemical cell"). This drives a small electrical current into your nerves, which you feel as pain.





Isn't it a shame we don't feel it as pleasure? I suppose it's for the best as we'd all start eating KitKats with the wrapper on.
Reply:Dead easy! - Its electrochemistry!





You are making an electrochemical cell, the foil is the electrode, your saliva your electrolyte and yes you are right! Your filings are your other electrode. You see foil is made of aluminium that likes to be Al3+ with a positive charge, your filings could be an Al alloy or silver that will have a potential difference to the Al foil to pass a charge between the two. When a charge is passed, you nerves in your teeth will feel it and it will hurt.
Reply:have no fillings so couldnt say.