I am a dentist.

My first question, why do you WANT to get your fillings replaced?

Regarding root canal treatment: It sounds like you are very misinformed by
people who do not understand dental treatment.
Maybe I can clarify.

Root canal treatment is performed when the nerve inside your tooth ether
begins to die or has already died. Causing pain and/or and abscess. this is
usually due to tooth decay (carries- a bacterial infection) getting too close to the
nerve or into the nerve or sometimes to trauma (ether a blow to the teeth or
micro trauma due to grinding, clenching, or multiple tooth drillings).
During the procedure the nerve is removed and the main canal space is shaped.
The main trunk of a nerve does have small branches which are removed with
irritants.
The canal is then sealed with inert cement sealers and a rubber type material
called Gutta Percha.
Root canal success is about 90%.
It is the only treatment to save your tooth if the nerve is dying or dead.

Your other option is "steel and sunshine" that's right, extraction. Now you
are left with a hole. leaving the hole will result in numerous problems such as
tooth shifting, bite changes, increased chewing stress on remaining teeth,
unsightly hole in your mouth (people do notice and judge) and a few others.
Replacing the missing tooth is usually 2-3 times more costly than saving it.
Hope this clarified a few things. If you have further questions, do not
hesitate to e-mail me.  [log in to unmask]

Alex Shvartsman, DDS, FAGD