INBDE (Integrated National Board Dental Examination) Practice Exam

The labial frenum is a small fold of tissue that connects the inside of the upper lip to the gum tissue. The muscle that attaches to this frenum is the orbicularis oris, which is responsible for controlling the movements of the lips.

Option A, the mentalis muscle, is located on the chin and is responsible for controlling the movements of the lower lip and chin. It does not attach at the labial frenum.

Option B, the buccinator muscle, is located in the cheek and is responsible for compressing the cheeks while chewing. It also does not attach at the labial frenum.

Option D, the superior pharyngeal constrictor muscle, is located in the throat and is responsible for constricting the upper part of the pharynx during swallowing. It is not associated with the labial frenum in any way.