Abstract: The invention relates to a covering device for covering the lips and labial angles and for holding the lips, cheeks and labial angles away from the rows of teeth in the mouth of a patient which comprises an elastic lip clamping element for external contact with the mouth opening, at least one elastic vestibular clamping element for inserting into the oral vestibule of the mouth of the patient and a film connecting the clamping elements, wherein the clamping elements are arranged along two opposite end regions of the film such that the inserted covering device is open towards the mouth cavity, wherein the vestibular clamping element comprises at least one section which extends in the sagittal direction anterior to the vestibular fold when the covering device is inserted.