The present invention relates, without limitation, to a buccal valve suitable for modifying the respiratory flow of a user, which comprises: a valve body (1), adapted to be arranged between the dental arches of the user, wherein said valve body (1) comprises one or more airflow passages (5) therethrough； and one or more valve flaps (2) configured to be connected to the valve body (1) and adapted to regulate the flow rate and direction of the airflow entering the buccal cavity proper through the airflow passages (5)； and so that, when the buccal valve is installed in the buccal cavity of the user, the one or more valve flaps (2) are positioned in the buccal cavity proper and exposed to direct contact with the tongue of the user.
