Types of Hearing Loss
Conductive hearing loss: 
This is a hearing loss caused by a problem in the outer or middle ear. It is called “conductive” because something is blocking the movement – or conduction – of sound into the ear. The canal can be blocked by earwax, infection, a tumor, or a foreign object. The eardrum can be damaged by injury or infection. In the middle ear, abnormal bone growth, infection or tumors can block the sound. Most conductive hearing losses are medically or surgically treatable.
Sensorineural hearing loss: 
This type of hearing loss is caused by a problem in the inner ear or the auditory nerve. When damage occurs to these areas of the ear, sound may not only be damped but also distorted. Also called "nerve deafness," it usually occurs in both ears. Often it's caused by aging or loud noise, or by injury, disease, infection, toxic drugs, or an inherited condition.
Mixed hearing loss: 
This type of loss results from a combination of both a conductive and a sensorineural hearing loss.