Veeners are thin, custom-made shells crafted of tooth-colored materials (usually porcelain) designed to cover the front side of teeth. This is an irreversible process, because it's necessary to remove a small amount of enamel from your teeth to accommodate the shell.
Sometimes a veneer might chip or fracture. But for many people the results are more than worth it. It is a great way to correct crooked , permanently stained, or gapped front teeth.