What Causes Numbness In Upper Extremities Bilateral, Hands, All Fingers And Thumb?

I have Hx with c3/4 diskectomy and fusion in 2005, past 2 years devolping muscular neck weakness, past 2 weeks experiencing numbness in upper extremities bilateral, increased throughout the night, numbness to hands and all fingers and thumb, except pinkie fingers. Seems that neck positioning and re positioning all night long prohibits sleep. Along with this is a constant crushing pain in both upper arms, regardless of when the numbness is present or not. for 2 days now my teeth are in pain as though they are set on a grinder.