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They may be having a causative or contributory role...
If it is recurring in the same site, local causes should be searched for - tooth near by may be irritating ../ at times, biopsy will be necessary..
If site and severity are varying, local and systemic causes should be looked for...Anxiety, vitamin deficiency
are the usual causes. Good oral hygiene
, vitamin and analgesic will heal...
/ Internist - any one can help...
Wishing speedy recovery