INBDE (Integrated National Board Dental Examination) 2025 – 400 Free Practice Questions to Pass the Exam

A chin cup is used for treating Class 3 mandibular excess, also known as prognathism. In this condition, the lower jaw extends beyond the upper jaw, leading to an underbite. By using a chin cup, which is typically part of orthodontic treatment, forces are applied to the mandible to help correct the skeletal discrepancy and bring the lower jaw into a more ideal relationship with the upper jaw.

Options B, C, and D are not correct in this context:

- Class 2 mandibular deficiency would involve a retruded lower jaw, which would typically be addressed with different treatment modalities such as headgear or functional appliances.

- Palatal expansion is used to address narrow dental arches or crossbites, focusing on widening the upper jaw rather than correcting the relationship between the upper and lower jaws.

- Molar distalization aims to move the molars backward in the dental arch, usually to create space or correct crowding issues, and is not related to treating a Class 3 malocclusion.