About a year after chemo I had signs of gingivitis, and had to have a root scaling done. NOT FUN (ok the laughing gas part WAS fun, but....) Onc and dentist both said 'yup, a side effect of having chemo'...now I use a proxy brush, floss, and a little toothpick thing to get around my back teeth...it's a pain in the neck! but better than that yuky root scaling procedure. And yes my teeth are very sensitive to hot/cold now.... Are you using a tarter control toothpaste? That will cause TONS of sensitivity pain in those whose teeth are sensitive. Also if you've used those over the counter tooth whiteners (crest strips) that is bad as well.
Please get it checked out....
"It's been worth everything I've been through,
To do what I do"
To Do What I Do -Alan Jackson, 2004