Eating eggshells cannot regrow your teeth.
Once you have lost your adult teeth which are your permanent teeth you cannot regrow them like you can baby teeth.
Our bodies have 2 sets of teeth when we are born and those are our baby teeth and our adult teeth.
Our baby teeth fall out between the ages of 6 to 8 years old and then we start having our permanent teeth come in.
The permanent teeth which we grow after our baby teeth fall out are the last teeth we will be able to grow.
So it's important to take care of your permanent teeth to prevent tooth decay and to keep your teeth.
There's no way to regrow teeth whether it's by use of eating egg shells or anything else.
However eating eggshells can help give your body calcium which can help keep your teeth strong and healthy as well as help keep your bones strong and healthy.