Thanks again Bryanna,

No history of accidents or getting hit in the mouth, but he did have a major filling (MO) on the side of #14 back in 2011. Also comparing panoramic x-rays from 2008 and 2013, it does appear there has been bone loss on the mesial area of #14 over just the past few years. Not sure if a possible fracture could have been there before the restoration or caused by the filling or after. But like you indicated, there does seem to be something going on there.

Our dentist did not mention anything about the sinus during another recent filling done on this tooth.