How long does it take for the tooth numbness to go away after endoscopic sinus surgery (FESS)?

About 3 months ago, I had endoscopic sinus surgery (FESS) on the maxillary sinus. I was told no nerves were cut during this surgery. However, I woke up 2 days later with numbness in my front teeth. After 4 weeks or so, I began feeling some pressure in these teeth and very mild electric shock sensations from time to time. I am worried that it has been 3 months and my teeth are still numb. The numbness seems worse in the morning.