Brief Answer:
Take symptommatic treatment meanwhile.

Detailed Answer:
Hi,
Welcome to health care magic,

There could be variety of causes of this sore spot like small boil or canker or inflammed papillae, which needs to be ruled out by examination of oral cavity.

But no need to be worried here as this kind of oral problems can be resolved with symptommatic treatment only.

During this night time your wife can take below treatment for symptommatic relief which can be available over the counter without prescription.

1) pain killer like tab.ibuprofen,

2) local anaesthetic gel and

3) listerine or chlorhexidine mouth wash for symptommatic relief.

4) Vitamin B complex with folic acid once daily

She can take this treatment for 3 to 4 days and in most of cases, lesion would start improving.

However,if your symptom does not improve within 2 to 3 days then you should see your primary health care doctor or dentist to rule out above causes as I mentioned.

Hope this information will help.

Regards,

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