Dear Lybrate user, yellowness of teeth may be due to extrinsic stains or plaque and calculus
deposits on your teeth. Hardened plaque deposits on teeth are difficult to remove with brushing. You need to undergo a professional cleaning/scaling treatment. It won't change the inherent coloration of your teeth but remove all the stains to give you a brighter and healthier smile. Consult your dentist
for a thorough examination.