Chronic pain is defined by the American Academy of Orofacial Pain (AAOP) as “Pain that persists when other aspects of disorder-disease have resolved, typically lasting more than 6 months or beyond the normal time for healing of an acute injury or pain”. In other words, the pain persists even when the initial reason for the injury or pain has stopped.
The exact mechanisms as to why some pain conditions heal normally and others develop into chronic pain are very complex and not completely understood by science. There are researchers around the world investigating the complexities of chronic pain. Though we have many answers, volumes of text books, and useful therapies for chronic pain, we are far from a full understanding.
Once the initial injury or insult to the bodies’ tissues (muscles, nerves, bones, blood vessels, etc.) has ended and an appropriate healing time has elapsed, yet the pain persists, the pain has become “chronic pain”. Chronic pain involves physical changes in the brain, spinal cord and the nerves and nerve junctions all the way from the brain to the pain site. This shift results in the pain source that was outside of the body, to now the pain being generated from within the body by the Autonomic Nervous System (ANS). These deviations also change how the brain and rest of the body process information to the body from outside sources (trauma, touch, hot, cold, etc.), particularly that of pain. Once these variations have occurred, treating the original pain source will be insufficient to alleviate the pain as treatment for chronic pain may be different than that for acute pain. The initial step toward managing chronic pain is obtaining a thorough evaluation with a qualified orofacial pain specialist. The earlier a chronic pain condition is treated, the more likely the outcome will be positive. The following are aspects of chronic pain that an individual may experience:
Referred pain – this type of pain is common with chronic conditions and is defined as pain in an area that is different from the site or the source of pain. For example; a person may have pain in a tooth, but the actual source of the pain may be an inflamed jaw muscle that is projecting pain to the tooth. The most well-known example of referred pain is that of during a heart attack the first pain experienced may be left arm pain or jaw pain.
Hyperalgesia – this is an elevated pain sensation to something that is normally painful. For example; a strong slap on the back can be uncomfortable or mildly painful, but a person with chronic pain and hyperalgesia may experience severe pain to the same slap on the back.
Allodynia – this is a painful response to an event that normally does not cause pain. For example; a hug from a friend does not typically elicit pain, though some individuals experience pain to simple gestures such as a hug, holding hands, a touch to the arm, chewing, talking, or singing.