Orthodontic Assistant Practice Exam

Where is the elastic placed to correct a Class II malocclusion?

1. Posterior to anterior

2. Anterior to posterior

3. On the molars

4. On the incisors

The correct answer is: Anterior to posterior

The placement of the elastic to correct a Class II malocclusion is critical in orthodontic treatment. A Class II malocclusion typically refers to a condition where the first molar of the lower jaw is positioned further back than the corresponding upper molar. To correct this, elastics are strategically used to apply force over the dental arch. When placing an elastic "anterior to posterior," the elastic is attached from the upper anterior teeth, such as the canines or incisors, and extends towards the back, generally to the lower molars. This configuration helps to pull the lower jaw forward or push the upper teeth backward, thereby encouraging the proper alignment of the dental arches. This specific placement is essential in guiding the movement of the teeth to achieve a more favorable bite relationship in a Class II malocclusion. The other options do not reflect the correct mechanics of elastic placement for Class II correction. For example, an elastic placed posterior to anterior would have the opposite effect, possibly exacerbating the malocclusion. Placing the elastic solely on the molars or on the incisors does not provide the necessary correction across the dental arch needed to effectively address a Class II malocclusion.