Hi, I understand this is no substitute for a proper check-up, but this is the most I can manage for the time being. I will see a dentist ASAP. I am wondering what the dark spot on my tooth could be. I am very worried, as I am prone to caries, even though I take good care of my teeth (the yellowness in the picture is from temporary food staining). Please ask any questions that would help provide useful and relevant information. Professional input is especially valued. Thanks.