I sincerely hope I am not too late in answering your enquiry.
Thank you so much for including a picture of your son's dental condition which helped me get a clearer picture of what he is experiencing. As Dr Geraldine has pointed out the presence of tooth decay and also explained the need for dental radiographs ( X-rays ), I will not repeat those points.
The white area noted on the upper left gums is likely to be part of an existing baby tooth. This is a condition called root fenestration. This is likely due to the tooth decay on the upper left lateral incisor ( the second tooth from the right, as shown in the picture) which I assume may have been present for some time now. His body has been trying to fight this decay and infection. Unfortunately, in the process, the bone surrounding that tip of the tooth's roots has started to soften and dissolve. This causes us to be able to get a peek at the tooth roots through the gums or what I like to call a "window" effect.
I agree with you that the black tooth should be removed at present. At present, there are minimal risks as compared to the potential benefits reaped if the decayed tooth were removed. While I agree that baby teeth are important space holders for the permanent teeth, I think at this juncture, ensuring decay and any oral infection is quickly brought to a minimum should be considered our first priority for your son.
A more detailed examination should be conducted by your dentist to ensure there are no other dental cavities to be managed - especially at the back molars. These are common spots where decay may occur. I recommend you bring your son to a paediatric dentist ( a specialist dentist who is specially trained to see children ) or at least a dentist who is comfortable managing children at a young age to get started.
Hope this has helped you clear up any doubts!
