Thanks for posting your query.
This pain came from a cavity that had virtually reached the root. you have to visit dentist
for root canal treatment
if there is no other cause i.e. fracture
Till then you can apply tea tree oil and a clean medicine dropper. With care, put 3-4 drops of the oil onto the affected tooth/teeth and leave it for at least 30 minutes. Tea tree oil has very good healing and antibacterial properties which would help alleviate the pain and kill the bacteria.
You only need about 6-8 tablespoons of salt and about a cup of water. Just wait for the salt to completely dissolve before you gargle the solution for about 1-2 minutes. Repeating the process a few times may be necessary to make the pain subside significantly.