The sliding caliper is an aid for evaluating the optimal tooth shape and size for the patient. Many years of experience have shown that there is a connection between the alinasal width and the shape of the patient's teeth. The sliding caliper can be used with the aid of the ToothScout app or the enclosed shape matrix to determine the PhysioStar NFC⁺, PhysioSelect TCR, PhysioSet TCR and PhysioSet CT anterior sets.