A clinical examination is necessary for correct clinical diagnosis. These white streaks on teeth can be due to plaque built up on your teeth. It can be an early stage of becoming a cavity. Excessive caffeine intake, drugs like tetracycline, caries, fluorosis, poor oral hygiene, smoking all can lead to discolored stains on the teeth. It is best to see your dentist and get checked. A clinical examination will definitely be helpful. I hope it helps.
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