The mouth guard, also referred to as a gumshield or mouth protector, is deﬁned as a resilient device or appliance placed inside the mouth to reduce oral injuries, particularly to teeth and surrounding structures. The mouth guard was constructed to protect the lips and intraoral tissues from bruising and laceration, to protect the teeth from crown fractures, root fractures, luxations, and avulsions, to protect the jaw from fracture and dislocations, and to provide support for edentulous space. The mouth guard works by absorbing the energy imparted at the site of impact and by dissipating the remaining energy. Custom-fabricated mouth guards are produced on a dental model of the patient’s mouth by either the vacuum-forming or heat-pressure lamination technique. Although any mouth guard is better than no mouth guard, custom-fabricated ones are the most effective. Contact our ofﬁce if you think your child may beneﬁt from a mouth guard.