These intraoral nighttime appliances can treat snoring acting directly on the mechanism which is the main cause of it, pushing the lower jaw in a forward position. Mandibular repositioning pushes forward also the tongue and the epiglottis, spacing them from the uvula, thus to solve soft tissues vibration during the airflow, that is what produce the snore sound. MAD appliances can be used for the treatment of sleep apnea (OSA) since they can solve the rear airways obstruction by restoring breathing capacity during sleeping time. The American Academy of Dental Sleep Medicine claims that the most efficient appliances are bi-maxillary type, custom-made by a dental lab and, furthermore, they must allow an additional advancement over the construction bite position, about 4-5 mm. There are all over the world, many different type of MAD appliances to treat snoring syndrome and sleep apnea: we have decided to accomplish, and improve, the elements for the realization of the most widely used appliances according even with the clinical and scientific proven efficiency. This is our proposal based on the requirements of any clinical specialist: appliance efficiency, high safety standards and stability and comfort for the patient.