Teeth may become stained or discoloured over a long period time. This can be caused by the consumption of wine, cola drinks, coffee and tea, food with strong pigments and smoking or chewing of tobacco. Teeth whitening, or teeth bleaching can make discoloured teeth become pearly white again. While this can be done at home, not all teeth will react positively to teeth whitening products. It’s always safe to have a professional whiten your teeth.