Brief Answer:
Supportive care only

Detailed Answer:
Thank you for asking

I read your question and i understand your concern. Diminishing of taste with metallic nature is attributed to recent sinus infection you hd as well as dental issues for the last ten years. Medications used for sinuses congestion also give such taste disturbance.

With complete resolution of sinus symptoms, this taste issue will respond too after a few days. Till then all you need is supportive care, good oral hygiene, frequent fluid intake, regular brushing, flossing and rinsing with garlic and salt water. Consulting an oral hygienist for other oral hygiene measures. Artificial salivary supplements can be tried to help taste and keep the dryness of the mouth checked.

I hope it helps. take good care of yourself and dont forget to close the discussion please.

regards
Khan

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