most common cause of conductive hearing loss
Common causes of conductive hearing loss include: 1  Cerumen (earwax) or foreign body in the external auditory canal. 2  Otitis externa, infection or irritation of the outer ear.  Exostoses, abnormal growth of bone within the ear canal.
Fluid accumulation is the most common cause of conductive hearing loss in the middle ear, especially in children. Major causes are ear infections or conditions that block the eustachian tube, such as allergies or tumors.