Sore Mouth, Apthae, ...

1. Natrum Phos 6x, 3 tablets after each meal to neutralize any acidity.
2. Apis Mel 30 in the morning and Ars Alb 30 in the night for 1 to 2 weeks to release toxins from the body - the fundamental cause of ulcers in the mouth
3. Pancreatinum 1300 (Solaray), available from Vitamine shops, one tablet during meal for 2 weeks to permanently fix the underlying acidity problem.
Only if all the 3 measures above fails:
1) Borax 30, 2 drops, twice a day till better