Ada,
I've had CRPS for almost 10 years and at after my last dental appt. my mouth started burning. My tongue is on fire all the time. Food is too spicy...American cheese is spicy. I've been told that it is possible for it to spread anywhere in the body, but that has been disputed as well depending on who you talk with.
I've been told my vitamin B is too low thus causing the burning sensation in my mouth. I've had the tests and my levels are perfect. There is no other explanation than CRPS. I shudder when the doctors blame everything on CRPS because not everything is related. This I feel is.
One of the specialists at the Chicago conference last year stated CRPS can go anywhere within the human body. This is a world renowned specialist and spoke specifically about women and childbirth, thus resulting in vaginal RSD and other issues. With specialists from all over the US there they would disagree on treatment modalities. Always in good humor and with grace and dignity of course. It was validating hearing them disagree as so many pain physicians do. I feel it is up to us to be advocates and it's okay to disagree with your pain physician on certain areas. My former (former being the operative word) felt CRPS does not spread.

Take care,
Bonnie