What is on my sons top front teeth? ?

Question

i have been brushing my sons teeth since he first had one with the baby tooth paste and about one month ago, we started noticing a yellowish coat over it. it doesnt coat the whole tooth but its on the two upper teeth? any ideas? im taking him to the doctor monday for a check up so ill defitnally be able to find out but this is driving me nuts!! we dont really give him anything sweet.. just the basics... baby food, yogurt etc.. so i dont know what i could of done to cause this....

thanks!!

Answer 1

It could be getting rotten