Welcome in H.C.M.
I have gone through your query regarding canker
sores of your kid and you are interested to treat it without applying anything locally over cankers.
Here I would like to suggest you that your child should be properly examined by physician and needs investigations also to identify the causative agent and the appropriate antibiotic which may given orally or by injections. At the same time he should also be investigated for diabetes
, blood protein, and deficiency of vitamins
. If any of these factors are there they should also be taken care of.