Hi,
There are multiple things that can cause this. I would have my TMJ and bite evaluated by someone who is highly trained in this field. I would have seen an Oral Surgeon as well and possibly have CT scans of the jaw. At times there are referred pains due to nerve impingement that can cause this pain as well.
Sinus tooth ache almost always involves upper posterior teeth. Please keep in mind that tooth ache is not always odontogenic. If your dentist can not identify structural pathology of dentoalveolar structure, seeing an orofacial pain specialist is advised.