Very good evening doctors. how exactly is complete opacification of the left frontal sinus treated? do you lose your sense of smell/taste from the treatment? is nasal packing required?

Opacification usually means the sinus is filled with fluid, often but not always due to infection. A decongestant spray or drops may be all you need, but an antibiotic may be required if you have other symptoms of infection, like pain, lots of nasal discharge, etc. Probably no need for packing, but each case is different. None of these is likely to alter smell or taste. Follow your doc's advice.