Snoring is generated in the area of the upper respiratory system. Caused by acceleration of the air flow when the respiratory tract is cramped (pharynx), parts of the soft tissue start to vibrate and cause the snoring noise. The Silensor-sl belongs to the mandibular advancement splints. These devices prevent the lower jaw to fall back during sleep. Clinical tests give proof of the effectiveness of mandibular advancement splints, amongst them also the especially comfortable Silensor-sl.Up to 40 % of the population in industrialized countries snore. The decreasing muscle tone during the sleep causes a norrowing of the upper respiratory tract. This narrowing accelerates the respiratory airflow, thereby various structures in the area of the upper respiratory tract start to vibrate and cause the snoring noise. So snoring is a mechanical process that can be counteracted mechanically. Here the dental therapy comes into action. Light or primary snoring do not have consequences on health whereas the rhonchopathy, the abnormal snoring, does.Sleep apnea is, at a certain level of severity, a serious disease that may cause not only sleepiness during the day but also serious systemic diseases. The apnea is a total respiratory stop. The obstructive apnea is a complete occlusion of the respiratory tract whereas in case of the central apnea the central respiratory reflex arrests.