The color of our permanent teeth is yellowish white and not white. So, they look yellowish only. But there are whitening treatments to lighten the color which can be done in a single sitting at a dental clinic Hope this helps !!!

clinical examination is must by doctor

Kindly visit dentist for clinical examination. Just brushing is not sufficient to keep teeth clean. If natural shade of teeth is yellow, they will appear yellow only

hi tooth color and appearance depends on various factors like internal factors such as changes during tooth formation and external factors depending on external stains or due to tooth material loss for knowing these clinical examination can determine the cause and reason so please do share some photos or take appoint from local dentist

Without a examination it's difficult to comment ,however there are lots of reason for such kind of clinical findings mainly enamel hypocalcification ,amelogenesis imperfecta ,fluorosis ... I advice u visit a dentist for a more precious answer

Please visit your dentist

It is difficult to diagnose without a clinical examination as it multiple factors can lead to this.