This is one of the best descriptions I have found on Trigeminal Neuralgia.  It explains where the trigeminal nerves are and the different views as to what causes the damage and pain.  It will also show the two different types of TN and how they differ along with treatment and surgery options.  I added this link to give you a quick medical understanding of the disease.  I encourage you to research specialist and hospitals to find the most current and best options for you or your loved one.  I will work on making a shorter and personal understanding of TN in upcoming post.