A 25 year old female patient is unhappy with her smile. Which of the following could be the reason for the patient’s chief complaint?

The smile arc is defined as the contour of the incisal edges of the maxillary anterior teeth relative to the curvature of the lower lip during a social smile. For best appearance, the contour of these teeth should match that of the lower lip. If the lip and dental contours match, they are said to be consonant. In a “nonconsonant” smile arc, the maxillary incisal edges are either flat or reversed relative to the curvature of the lower lip. A flattened smile arc is less attractive in both males and females.