I just found this site and read this reply and wanted to add that I use the peroxide to brush my teeth. First I wash out my mouth with the peroxide, then spit the peroxide on my brush and then brush away. I make sure I don't swallow any. Sometime I will do the same thing with the mouthwash that is supposed to stop plaque build up and then use the peroxide again.
I started rinsing my mouth with hydrogen peroxide 3% and noticed a difference within a couple of days!! I don't know if it stopped the gums from receding but it sure took the sensitivity away. I would definitely recommend trying. I rinse a small amount twice then rinse with water once a day. I don't even do it everyday and I haven't had any pain
For years, when I get sensitive gums, bleeding or otherwise inflamed, I rinse my mouth with HP. After the rinse I also brush my tongue while the HP is still bubbling in my mouth. Mouth sores disappear in about a couple of days.