Will My Bearded Dragon's Tail Grow Back?
The short answer is "no".
It is a common misconception that beardies are able to drop their tail and regrow it. Your bearded dragon cannot drop their tails at will as a defense mechanism nor will their tails regrow even if they lose them through other means such as injury or an accident. Unlike some other species of reptile such as leopard geckos who have the ability to drop their tail as a defense mechanism so they can escape a predator and then regrow their tail, bearded dragons lack the ability to do so and instead have other ways of defending themselves like black bearding, biting, tail whipping and puffing themselves up to make themselves look bigger.
They can lose their tail whether it be through injury or through other means but their tails will simply heal up on the end where the loss has occurred and stay that way. If your dragon suffers an injury to its tail it is important that you treat the injury as you would any other, by keeping it clean and pursuing veterinary attention if the injury is serious enough to warrant it.