American Board of Orthodontics (ABO) Practice Exam

Class II elastics are often used in orthodontic treatment to help correct the relationship between the maxilla (upper jaw) and mandible (lower jaw). When Class II elastics are employed, they create a continuous force that pulls the mandible forward while simultaneously exerting a backward force on the maxilla. This biomechanical interaction can lead to a restriction in the forward growth of the maxilla.

The rationale behind this treatment effect stems from the way elastics influence the position and growth of the upper jaw. Specifically, when the elastic forces are applied, the tension may inhibit normal maxillary growth due to the mechanical constraints imposed by the traction of the elastics. Research and clinical observations have indicated that there is often a decrease in the vertical and anteroposterior dimension of maxillary growth when Class II elastics are used.

Understanding this effect is crucial for planning orthodontic treatments effectively, as it can influence the long-term stability and position of the teeth and jaws. It also highlights the importance of monitoring growth patterns in growing patients who are receiving this type of treatment.