Brief Answer:
Yes it could be infection or some thermal injury.

Detailed Answer:
Hi

Thanks for writing in.

I would like to tell you that palate is very sensitive area & there can be various reasons fore sore roof of mouth:-
- excessive hot or spicy food might cause burning of palate resulting in soreness
- any infection in tooth might lead to abscess causing palatal soreness
- burning mouth syndrome
- oral ulcers due to vitamin deficiency or some other reason
- any local irritant or sharp filling in that region

A physical examination is necessary to isolate the cause.

I suggest you to apply some topical anaesthetic gel over it like dentogel. Also take multivitamin supplements. If symptoms don't heal in the next few days, visit a dentist for examination.

Need not worry.

Hope I answered your query

Wishing you good health

Regards
Dr. Neha Sumra

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