By Jayne Rutledge Onychomycosis, the medical term for a fungal infection that occurs on the toenails, is a condition that results in a thickened nail. It can also cause the edges of the nail to become brittle and yellowed. The condition usually becomes known when a white spot appears. Eventually, it will spread to the entire nail and possible other nails. This fungal infection can be hard to get rid of and can easily return if it is not treated properly. Laser treatment for toenail fungus is a fairly new method that may get rid of fungal infections...