Brief Answer:
gum infection, decayed tooth, teeth cleaning

Detailed Answer:
Thanks for your query. I have gone through your query.
As far as the bleeding from the tooth is concerned, I have the following possibilities.
It can be because of the gum infection secondary to deposits over the teeth.
The other possible cause can be because of the pulp polyp secondary to decayed tooth.
Nothing to be panic, consult an oral physician and get it evaluated.
If it is secondary to gum infection, you need to get the teeth cleaned. If it is secondary to decayed tooth, you need to get the tooth root canal treated.
You need to get the complete blood investigations done to rule out any bleeding disorders.
I hope I have answered your query. If you have any queries reply me back. For better diagnosis and treatment plan, please upload the images of tooth in problem.
Take care

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