Thank you very much sir for your kind reply
Hello,
It can be due to canker sores. They are generally caused by Stress, tissue injury, eating certain foods – including citrus or acidic fruits and vegetables or underlying health condition, such as an impaired immune system; nutritional problems, such as vitamin B-12, zinc, folic acid, or iron deficiency; and gastrointestinal tract disease.
Avoid spicy or acidic foods during this time.You can use topical ointments like numbing ointments, such as benzocaine (Oragel), anti-inflammatory (steroid) gels,benadryl allergy liquid mouthwash,oral preparations of steroids and vitamin supplements.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.