Hearing loss is the partial or complete loss of hearing that can be caused by many different factors. The types of hearing loss are commonly characterized into three groups: conductive, sensorineural, and mixed. Conductive hearing loss is caused by problems in the ear canal, eardrum, or middle ear and/or its bones. Sensorineural hearing loss is nerve-related and due to problem of the inner ear. Mixed hearing loss refers to a combination of the other two groups. Some hearing loss can be successfully treated with medications or surgery.