I was originally sent to a dental specialist, who deals with facial pain situations.

He diagnosed TMJD (tempomandibular joint disorder) and then trigeminal neuralgia.

A year later with picking at doctors, I was MRI'ed (facial pain was changing/not going away) and voila, Multiple Sclerosis.

Trigeminal Neuralgia can exist on it's own, independent of MS, however it can be a symptom of MS as well.

I hope you're able to find some answers for your own situation and get relief from the pain.