Natural Home Remedies for Mouth Ulcers These ulcers occur periodically and heal completely between attacks. In the majority of cases, the individual ulcers last about 7–10 days, and ulceration episodes occur 3–6 times per year. Previous Next Pages: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 2017-10-14 spiel