In biology, poisons are substances that cause disturbances in organisms, usually by chemical reaction or other activity on the molecular scale, when an organism absorbs a sufficient quantity. The fields of medicine (particularly veterinary) and zoology often distinguish a poison from a toxin, and from a venom. Toxins are poisons produced by organisms in nature, and venoms are toxins injected by a bite or sting (this is exclusive to animals).
A problem with your jaw. Earache is occasionally caused by a problem with the joint of your jaw bone (where the jaw meets the skull). This is known as temporomandibular joint pain and can be caused by problems such as arthritis or teeth grinding.
6. Tooth infection: Sometimes a bacterial infection of the tooth can cause ear in the pain. A cavity in the tooth, chipped or broken tooth, all of these can cause tooth decay allowing bacteria to infect the pulp. The infection most of the time spreads to the bones supporting the tooth and causing severe pain.