Fig. 2From: The maxillary incisor labial face tangent: clinical evaluation of maxillary incisor inclination in profile smiling view and idealized aestheticsFemale smiling profile view; TrH, true horizontal line; TrV, true vertical line; red vertical line is the tangent to the labial face of the maxillary central incisor crown, and the measured angle is the inclination of the labial face tangent in relation to the TrH lineBack to article page