Brief Answer:
depends upon how long it has been there

Detailed Answer:
Hello and thank you for your question.
If the sore has not been there very long then it is probably a viral ulcer and will resolve on its own. Most small sores on the tongue go away without any treatment. Make sure that you are brushing your teeth regularly and keeping your mouth clean to decrease the risk of infection.
If the sore has been there for a while you may need to see a doctor for an exam of it or even a biopsy, some sores can be an early stage of cancer and will need excision or treatment.
If the sore area is white and it scrapes off it may be thrush and that can be treated with oral antifungal medications. If it is white and does not scrape off then that could be a precancerous condition called leukoplakia and you would need to see a doctor for that for a biopsy.
I hope it resolves on its own soon,
Dr. Robinson

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Brief Answer:
yes, warm salt water is good

Detailed Answer:
It is probably just a small wound then. Warm salt water is good if it seems to ease the discomfort. The mouth and tongue are remarkably good at healing up small wounds so it will probably resolve in a week or so.
There is not much you can do to speed up the process but warm salt water will not hurt anything and could be comforting to the wound.
Regards,
Dr. Robinson

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