Brief Answer:
Needs clinical Examination and investigation.

Detailed Answer:
Hello XXXX ,

Thanks for consulting Healthcaremagic .
This is Dr. Priyanka Tiwari answering your query .

Read your query as you have numbness and tingling below the corner of right side of mouth and area of teeth this could be due to some reason which include :
- Any Recent dental procedures you have gone through and keeping your mouth open for long period of time can cause some stress on corner of mouth . In addition if you are numb for any dental procedure on right side of mouth .
- Numbness on one side of mouth can be due to pressure on nerve can come from swelling or abscessed tooth or infected tooth pressing the main nerve of lower jaw .
- Medication like if you are taking for Dry mouth or Diabetes . It can be drug induced also .
- Vitamin deficiency or you might be getting canker sore it might cause tingling sensation a day before they appear.
- Stress induced .

For this I will suggest you to take Vitamin supplements by consulting with local doctor . Avoid stress and keep well hydrated .

If symptoms persists aforementioned then consult oral surgeon or Physcian for examination and investigation like Complete Heamogram or Blood chemistry if needed to rule out cause of numbness .

Hope I have answered your query .
If you have further query feel free to ask I will be happy to help.

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