Thank you for your reply. And how do you see my upper teeth? Both my upper and lower regions are sensitive to cold/hot beverages.
Also, I'm relatively young (23); is there a chance that it will come again after treatment, on its own, even if I maintain good hygiene measures?
By the way, I neither smoke nor drink coffee or alcohol. I got it from tonnes of sugar and zero brushing, to be honest, but I have already began to change that.
I upload a third photo that I believe is crisper than the previous ones: