<s>[INST] Hi, I noticed a small hole forming between my teeth a few days ago. I pretty much brushed it off and made sure I brushed over it and trued cleaning it out with mouthwash and today I woke up and it was black. I can show you a picture through email if it helps [/INST] Thanks for your query, I have gone through your query. The black discoloration over the teeth could be a decay, consult an oral physician and get it evaluated. If it is dental caries, then get it restored witChatDoctorposite or silver amalgam restoration. Sometimes the normal brushing and use of mouth wash will not help when the grooves are deep in the chewing surface. I hope my answer will help you, take care. </s>