US Patent 10292788 Film clamping element

The invention relates to a film clamping element, in particular for carrying out dental treatment in the mouth area of a patient, comprising a vestibular ring (14) and a lip ring (12), between which and optionally beyond which a film (16) extends. The film is held in a stretched manner by the rings, and the film (16) and the rings are elastically deformable, in particular the film and the rings can be pressed together into a substantially oval shape. The invention is characterized in that the vestibular ring (14) has a recess on at least one circumferential point, the width of said recess being greater than the width of a frenulum and smaller than the radius of the vestibular ring (14).