Low back pain in the dental profession is quite prevalent. I have written oLn the pervasiveness of this, and the development of it, in previous issues of Oral Health.
The implications of such a development within the dental professional can lead to quite an amount of aggravation and pain.
In previous articles written in Oral Health, I have shown the long-term effects of your profession on your body, and the hindrance not only on quality of life but quality and length of time, actively practicing within the profession.
As a dental professional, to maintain the length of your career and more importantly the long-term health of your body, certain measures need to be taken.
In the referenced articles, I outlined what mechanical contributors lead to the development of chronic low back pain within the dental profession, which can be referenced for more detail. Maintaining the prolonged seated posture creates alterations in tension in the muscle tissue, as well as increased laxity within key structural ligaments that eventually leads to disc bulges and herniations. It is believed that this is the predominate reason for the development of chronic low back pain in the dental professional.
However, maintaining and more importantly, rehabilitating from low back pain is more complex then simply strengthening muscles around the back. The body is complex, in fact, it has become quiet evident that our body functions more as a system as oppose to mechanical model.1 Therefore, only addressing the mechanical contributors to your pain would not provide a comprehensive and complete level of care. This likely is what contributes to such a high reoccurrence rate of low back pain in the general population and amongst dental professionals.2
Beginning in the times of Rene Descartes, pain was considered to be the simple consequence of the brain reading pain signals, called nociception, from the body. Under the Cartesian view, pain is an input from the body, which the brain perceives passively like a paper receiving ink. Based on this idea, we would expect to see a simple one-to-one relationship between tissue damage and pain. However, that is clearly not the case. Examples of this are those who experience phantom limb pain, or the fact that more then 60 percent of people are asymptomatic in the presence of disc herniations and disc bulges.
What may seem logical has not been treated with logic in the medical community – that logic being that chronic low back pain requires a multi-dimensional approach. Approaching rehabilitation and maintenance from strictly a bio-mechanical approach, as has been the case with the use of ergonomically designed equipment in the dental office, is insufficient.3 The New South Wales study demonstrated that the implementation and use of ergonomically designed equipment has been statistically insignificant in the reduction of the symptoms of low back pain.3 One of the key pieces to the health of your body as a dental professional involves the inclusion of the metabolic and neurological system.4,5
As a dental professional, you are asking your body, and specifically certain muscles, to maintain prolonged postures. To be able to maintain the functioning of these tissues and what is being asked of it, your body at its most basic level requires oxygen and a continual supply. As we age, in particular beginning in the end of our third decade and especially into our fourth decade of life, the walls of our blood vessels begin to age as well. A significant amount of research was done from the late 80s to the last decade, showing that as we age, there is a reduction in blood flow. Even if heat was introduced to a given area (which would normally promote blood flow), as you age, your body’s ability to maintain vasodilation in the presence of heat is diminished noticeably.6,7 Oxygen transportation is a passive phenomenon and if there is a reduction of vessels in a given area, or degeneration of the vessel wall, oxygen is unable to diffuse to all the required tissues.
Improving oxygen transportation requires increasing capillarization in the body and this is done primarily through aerobic conditioning. As you improve aerobic conditioning in the body, the body begins to increase capillary density and thus improves oxygen diffusion to needing tissues. And, in the dentist’s case, to all the tissues in the low back area.8-10 Based on the work of Dr. Maffetone in the chart below, you can find the guideline to follow to improve capillarization in order to increase oxygen transportation to the needing tissues.11 Dr. Maffetone has worked with countless athletes and individuals with heart disease, or indicators of such, over three decades with this formula successfully. It is important to understand that to create the physiological change that is needed, the body requires anywhere from two to six months. Consistency is required.
Metabolic function is critical and includes your ability to digest foods and your body’s absorption of foods, which also requires attention but is beyond this article. However, the importance of the metabolic system is critical to understand. In research done by Duruoz, the importance of the metabolic system is shown when it was seen that those who have low back pain take longer to recover when metabolic dysfunction exists.12 So, if you rely solely on the mechanical approach of introducing only corrective exercises, you may not reach your goal of pain free living.
Understanding pain is also important. We have already shown that there isn’t a one-to-one relationship with tissue damage and pain.
Another big contributor to not only the development of low back pain, but also to its persistence, is the involvement of the autonomic nervous system.13 The autonomic nervous system has two subsystems: the sympathetic nervous system (fight or flight) and the parasympathetic nervous system (rest, relax). Dr. John Sarno has written extensively on his belief that emotional factors have a great deal of impact on the development of low back pain. Although his explanation as to why has been scrutinized, the involvement of the autonomic nervous system has not.14 With increased stress, anxiety, anger and injury causing pain, sympathetic tone in the body increases. This leads to increased tension within the tensional properties of the body, the muscles, as well as the connective tissue, like the fascial tissue, that also encompasses contractile properties. There is also a marked vasoconstriction of the above mentioned important blood vessels, thus reducing the possibility of transporting oxygen to the required tissues. Microvascular blood flow is controlled by sensory nerves and the sympathetic nervous system.15
The eventuality of the required tissues in our back not receiving the oxygen needed is alterations in the chemical environment surrounding free nerve endings and activation of the nociceptive pain fibres, called C fibres. Activation of such nerve fibres sends nociceptive signals to
the brain, containing information about possible damage. In some case,s that damage could be only a minor strain. However, no pain is felt yet. First, the brain interprets this information and decides whether pain would be a good way to encourage action that will help protect and heal the potential damage, so in some cases this leads to further tension in the area to limit movement that could cause harm. The brain considers a huge amount of factors, aside from just the nociceptive signals in making this decision, and no two brains will decide the same thing. Many different parts of the brain help process the pain response, including areas that govern emotions and pats memories. The neuromatrix, as was coined by Melzack and Wall, is simply the combination of brain areas that produce pain when activated. Given the complex nature of the multiple aspects of the brain that get involved, signals from the body and to the body can be upregulated, inhibited, interpreted and misinterpreted in a stunningly wide variety of complex and interactive ways.16
This explains why placebos work; why someone can experience pain with no tissue damage; why someone can have significant tissue damage without pain and why pain can be significantly affected by non-nociceptive sensory information, like thoughts, memories, emotions and social interaction.
Low back pain in the dental profession goes beyond the bio-mechanical load the profession puts on the body. This is confirmed by studies that show job satisfaction as an excellent predictor of low back pain, an even better indicator then MRI results showing herniated discs or torn rotator cuffs.
This is just a brief look at what contributes to your low back pain, but it is important to realize that your low back pain isn’t as simple as fixing your posture, or doing a particular exercise. Otherwise, the execution of the above mentioned would cure all.
Addressing psycho-emotional factors within each person is vital. Dr. Sarno has gained popularity by ‘curing’ back pain by working on only the expression and awareness of underlying emotional regressions. This is demonstrated by a reduction in sympathetic nervous system activity, and contribution to increase dilation of blood vessels. Improving oxygen transportation through improving capillarization allows for the oxygen to diffuse to the required tissues and more frequently, to keep up with the demands of your profession. And finally, it is still important to address the bio-mechanical requirements that your profession places on your body. Through clinical experience, full rehabilitation from low back pain, and prevention of low back pain only occurs when one engages in a more complete integrative approach.
In the second edition of The Dental Manual, I outlined all the contributing factors to the development of the musculoskeletal disorders within the dental profession, from low back pain to neck pain to shoulder pain. As well, I go through, in detail, the metabolic steps needed through exercise and nutrition, neurological steps through practices that can be taken up on your own and through specific therapeutic interventions, as well as bio-mechanical steps with videos of the execution of the specific corrective exercises required for the dental professional.
For questions or inquiries regarding purchasing The Dental Manual , feel free to contact me at: firstname.lastname@example.org.OH
Dr. Mahmoud Zaerian is a practicing chiropractor and neurofunctional sports practitioner in the city of Toronto. He has been in the health field for over 15 years working with many of our Olympic athletes including our Women’s Olympic Hockey team and Gymnastics Canada. He has spent the last eight years researching and working with dental professionals to restore health and pain free function in their body. Dr. Zaerian has written several articles on maintaining the health of the dental professional as well has spoken at the Annual Spring Meeting in Toronto and has been asked to speak at the California Dental Association Annual Meeting in Anaheim. He currently is one of the instructors at the McMaster University CMA Program, and has created The Dental Manual, a comprehensive written and video manual for dental professionals for restoring and maintaining health in their body. The Dental Manual includes video instructions and correct exercise execution as well as guidelines for an integrative approach to the health of the dental professional. You can contact Dr. Zaerian at (416) 837-4065 and
Oral Health welcomes this original article.
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