Laser Treatment of Canker Sore How do we treat canker sores (Apthous Ulcer)? Treatment is pallative, for comfort only. These lesions will disappear completely in 7 – 10 days with or without treatment. The problem is these ulcerated lesions can be quite painful! For a Small Lesion OTC topical anesthetic, (contains benzocaine, e.g. Orabase with […]