Oral devices are dental appliances designed to be worn in the mouth for various purposes, including improving oral health and enhancing sleep quality. Common types include mouthguards, which protect teeth during sports, and retainers, which help maintain teeth alignment after orthodontic treatment. Another significant category is mandibular advancement devices, used to treat sleep apnea by repositioning the jaw to keep the airway open during sleep. These devices are typically custom-fitted by dental professionals to ensure comfort and effectiveness, making them an essential part of dental and sleep health management.