I would consider seeing your MD first and if you can not get an answer I think you need to see your dentist. I have no idea what this might be coming from.
Factors associated with altered taste(dysgeusia)
Acute necritizing gigivitis
Chorda typani injury
Drugs, especially antibiotics
The information is quoted from: oral pathology,clinical pathologic correlations, page139, 3rd edition, saunders, written by Joseph A, Regezi, James J, Sciubba,