Do gums grow back to fill the spaces (black triangles) between teeth? (photo)

I went to the dentist a month ago and had a scale and polish to remove tartar. After that, I saw gaps that were never there. I had an x-ray done and, fortunately, I have no bone loss nor periodontal disease. My dentist said that I should worry more about cleaning my teeth properly rather than gum recession and the spaces between my teeth but they look ugly. The first two is quite small but the last one is bigger. Will my gums grow back to fill the spaces? Or at least, the smaller spaces?