Brief Answer:
Black hairy tongue

Detailed Answer:
hello and thanks for consulting HCM.

I have seen your report and medical history.it seems to be the case of black hairy tongue.it occurs due to enlargement of taste buds. Due to the surgery you might not have maintained hygiene.

I would advice you to maintain proper oral hygiene.
take multivitamin supplement like A to Z.
taste buds can get enlarged due to irritation.
quit smoking if you have the habit.
use antiseptic mouthwash .

I don't think you have to worry. It will subside as oral hygiene is maintained.

Hope this answer helps.

Regards
Dr. XXXXXXX

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