Sharp ear pain can have a variety of causes, some of which might not be related directly to the ear. Ear infections are relatively common, and many earaches can originate from infections in the middle ear, the ear canal or, in some instances, the bone behind the ear. Ruptured ear drums and airplane ear are additional ear conditions that can directly lead to sharp pain in the ears. Other indirect causes of ear pain include toothaches or certain jaw conditions, such as temporomandibular joint (TMJ) syndrome.
Most instances of sharp ear pain are caused by fluid buildup in the Eustachian tubes. This can have a variety of causes, including allergies, the common cold, flu, excess mucus or exposure to irritants such as tobacco smoke. Prolonged fluid buildup will most likely lead to infection, especially in children, which will exacerbate the buildup and lead to worse earaches. This is because bacteria or viruses infect the lining of the ear, keeping the fluid from draining out as it normally would. Bacteria then flourish in the fluid, aggravating the infection and causing increased, painful pressure behind the eardrum.
Several parts of the ear can become infected. Infection of the middle ear, also known as otitis media, tends to be most common. Swimmer's ear, or otitis externa, is an infection of the ear canal. Consistent exposure to water often leads to a breakdown of the skin in the ear canal, opening up the path for bacteria. Infection of the bone behind the ear, or mastoiditis, can also be a cause of sharp ear pain, and it most commonly originates from acute, untreated otitis media.
Ruptured eardrums also cause pain in the ears. They can result from infection but are more commonly caused by perforation or loud, explosive noise. They should at all times be kept dry during the healing process to prevent infection. Most mild cases will heal in a matter of weeks, but more serious cases might require surgery.
Barotrauma, commonly experienced as airplane ear, refers to changes in air pressure that disrupt the equilibrium in the ear. In most cases, high pressure air is caught in the auditory canal, either from ear wax or from scuba equipment if it is being used, and severe barotrauma can lead to rupturing. For this reason, flying with a severe cold or flu is also not recommended, because the blocked Eustachian tubes combined with the change in air pressure can be enough to tear the eardrum.
Tooth and jaw afflictions are common indirect causes of earaches. This is because the facial nerve, specifically around the upper molars, is closely connected to the ear. Chewing under hot and cold temperatures can exacerbate the sharp ear pain caused by toothaches, and the pain can be chronic or sporadic. Often, the most effective relief for this type of referred pain is simply treating the underlying problem that the tooth has.
The temporomandibular joint is especially close to the ear canal. As a result, untreated TMJ syndrome can be a consistent source of sharp ear pain. There tend not to be many effective sources of short-term pain relief for TMJ syndrome, because the pain is primarily based in the nervous system and does not respond well to most drugs.