Hello sir, Please correct your way of brushing first use a soft tooth brush . Get a proper scaling and polishing things can improve with this if it doesn't improve go for minor surgical procedure.

If your black triangle are small and you only have mild gum recession caused by gum diseases you may be able control things by improving your oral hygiene  routine. 2 if you are unhappy about the appearance of your black triangle we can build up your teeth by using a tooth coloured restoration.

Good morning Dear Thanks for the query As per your words you are concerned with the black triangle in interdental area.. Treatment for the same is: First of all stop brushing aggressively start using medium or soft tooth brush or brush gentelly. Visit a Periodontist(Gum Specialist dentist) he will do the professional cleaning and will guide you how to go through further based on your tissue response after cleaning.. Sometime with cleaning it can be covered if not than you mite have to undergo minor surgical procedure for the correction of the same..(Coronally displaced flap).. Regards Dr. Aman Bhatia Chandigarh www.dentafix.in

Such a minor triangle is difficult to treat. I suggest you leave it as it is.

These black triangles as I understand from the photograph that you have posted appears to be the spaces developed between your teeth largely due to interdental bone loss. There are various reasons for this and a few treatment options too. These "black triangles", as you call them, can be treated by gum surgery or by veneers/ laminates. Regarding the aggressive brushing technique that you use, kindly stop it immediately. Consult a dentist who would teach you the correct brushing method and suggest the best treatment modality for your problem.