Replacing your teeth is not an easy thing, and even if you invest huge amount you cannot get the beautiful healthy teeth back. So it is better to take safety precautions to maintain the long life of your teeth.
American Dental Association gave some recommendations through which you can protect your teeth. They prohibited Nail biting and said that it is not only harmful for your nails and beauty of your hand but it also damages the protective enamel layer of teeth.
They also recommended the use of soft bristle toothbrushes and asked not to use force while brushing your teeth.
Eating too cold water or chewing ice is also quite harmful for teeth, they also said that use of sweets and chocolates should be limited.