Conductive hearing loss occurs when sound is not conducted efficiently through the outer ear canal to the eardrum and the tiny bones, or ossicles, of the middle ear.

Conductive hearing loss usually involves a reduction in sound level, or the ability to hear faint sounds. This type of hearing loss can often be medically or surgically corrected.

Conditions associated with middle ear pathology such as fluid in the middle ear from colds, allergies (serous otitis media), poor eustachian tube function, ear infection (otitis media), perforated eardrum, impacted earwax (cerumen), infection in the ear canal (external otitis), presence of a foreign body and absence or malformation of the outer ear, ear canal, or middle ear.

Degree of Hearing Loss
Degree of hearing loss refers to the severity of the loss. There are five broad categories that are typically used. The numbers are representative of the patient's thresholds, or the softest intensity that sound is perceived:

Normal range or no impairment = 0 dB to 20 dB
Mild loss = 20 dB to 40 dB
Moderate loss = 40 dB to 60 dB
Severe loss = 60 dB to 80 dB
Profound loss = 80 dB or more