Best Answer: People have always argued what the best oil out there is. And most people either go for royal purple, castrol, and mobil 1. I personally choose Mobil 1, but the choice is really opinion based.
The sores may occur singly or in groups and vary from about 1/8 inch to 1 -1/4 inch in diameter. The sore may be painful for three or four days, but complete healing usually takes ten to fifteen days. Canker sores may recur many times each year. Causes: No one knows what causes canker sores. They may be caused by a virus, may be a form of allergic reaction or may result from an auto-immune condition (meaning that the body has developed an immune reaction against its own tissue).
Herpetiform canker sores are uncommon and usually develop later in life, but they're not caused by herpes virus infection. These canker sores: 1  Are pinpoint size. 2  Often occur in clusters of 10 to 100 sores, but may merge into one large ulcer.