What makes up the medial one-third of the external auditory canal?

The medial one-third of the external auditory canal is composed of bone. This part of the canal is situated closer to the tympanic membrane (ear drum) and transitions from the cartilaginous outer portion of the canal. The bony structure provides a rigid framework that supports the ear canal and protects the inner ear structures.

In contrast, the outer two-thirds of the external auditory canal is made up of cartilage, which offers flexibility and mobility. Understanding this anatomical distinction is crucial for hearing instrument specialists as it relates to examining, fitting, and managing hearing aids, as well as addressing any potential issues related to ear health and hygiene. This knowledge also aids professionals in understanding how sound travels through the ear canal and how various materials interact with the structures of the ear.