The present invention relates to a mouthpiece device which is for the use with the treatment of obstructive sleep apnea syndrome comprises at least one main air channel (2) which is provided at the outlet of the mouth and enables air passage into the mouth, at least one side air channel (3) which is provided at the outlet of mouth for supporting the main air channel (2), and which enables air passage into the mouth and air discharge outside the mouth, at least one one way valve (4) which is placed inside the main air channel (2), and only allows air passage by preventing air discharge from the main air channel (2), at least one protective plane (5) which is between the inner part of the lips and the outer surface of the teeth, at least one palate chamber (6) which extends inside the mouth by widening in the rear part of the protective plane (5), at least one tongue chamber (8) which is placed inside the palate chamber (6), at least one vent (9) which is provided on the tongue chamber (8) and creates vacuum effect inside the mouth, at least one sensor (12) which measures the carbon dioxide and oxygen levels in the air exhaled by the patient, and controls breathing, at least one palate extension (13) which extends from the palate chamber (6) towards the soft palate, and which electrically stimulates the palate when the sensor (12) detects the patient stops breathing.La présente invention concerne un dispositif de type embout buccal qui est destiné à être utilisé pour le traitement du syndrome de lapnée obstructive du sommeil. Le dispositif comprend au moins un canal dair principal (2) qui est prévu au niveau de la sortie de la bouche et permet à lair de passer dans la bouche, au moins un canal dair latéral (3) qui est situé au niveau de la sortie de la bouche pour supporter le canal dair principal (2), et qui permet à lair de passer dans la bouche et dêtre évacué à lextérieur de la bouche, au moins une valve anti-reflux (4) qui est placée à lintérieur du canal dair pr
