I've recently noticed that along the gumline of several of my teeth there are little grooves, like the enamel is worn away. Some of them just feel rough but others are kind of sensitive and it's really unpleasant to touch (of course I keep doing it anyway). Any ideas what that might be or problems it may point/lead to? Please don't say cavities 








I'll try to be more gentle and loving to my gums. I probably am brushing too hard as it seems like my teeth feel less clean these days, even after brushing.