The Silensor-sl consists of one splint for the upper jaw and one splint for the lower jaw. The lower jaw is either held in a predetermined position or advanced by 2 connectors that are fixed laterally to the splint. The Silensor-sl thus counteracts the narrowing of the respiratory tracts. The velocity of the inspired air decreases and so do noise-generating vibrations of the soft tissues. With the Silensor-sl jaw movements are possible but no falling back of the lower jaw. With this function the Silensor-sl is a comfortable and at the same time effective snore guard. Clinical tests have shown that the advancement of the lower jaw considerably reduces snoring at more than 80 % of the patients and may reduce the apnea index at up to 50 %.