Paresthesia Quandaries: thoughts?

I had two weird cases of paresthesias this month, one involving a bone graft, and I am hoping that the group could offer insight.

Case 1: Tooth #15 was prepared for a crown. 36 mg of articaine was used via infiltration. Impressions were taken, temporary seated and the patient left. The next day he had bilateral paresthesia of his tongue. He stated that when he was younger he developed an allergy to cinnamon that would do the same thing. Three weeks later he returned for the permanent crown and at that time the paresthesia had diminished by 40%. Question: What could cause such a reaction? Temporary, cement or other materials?

Case 2: I had a patient with a bridge from 20 to 18 (Lower left second molar to lower left second premolar). The molar fractured and was not restorable with failed endo, split root. I sectioned the bridge, removed the molar and granulation tissue. I grafted a composite of FDDB and FDMB with calcium sulfate hemihydrate. I placed a cytoplast single PTFE barrier and the patient was to return in 4 weeks for the removal of the barrier. Upon return he reports that there are times when his jaw œgets cold and becomes numb (along the path way of the inferior alveolar nerve). It only happens when he is physically active. He also gets referred pain to the TMJ and upper left molar area. He states he has a history of TMJ problems. I took an x-ray at the 4 week mark to see if there was anything to see. What do you think is causing these strange symptoms?