Receded gumline at one back tooth from overbrushing. Any hope for regeneration?

I've just been to my dentist yesterday. He said I got a "10 out of 10" because I have great teeth and gums, no cavities, floss regularly, etc. I apparently overbrushed at one point and wore the gum away at one back tooth. Now it's sensitive to cold; I now have a special toothpaste for it. I'm not satisfied with that, though, so if I massage my gums, is it possible that this will grow back at all? It seems like the official answer is "no." Has anyone here had this problem or known someone who has? Any solutions that don't involve surgery?