The term “dental pain” typically brings to mind uncomfortable patients getting Novocaine injections and the unsettling whine of the drill while having a tooth restored.
But the repetitive body positions that dentists and dental hygienists assume during treatment can result in injuries that cause considerable pain. Chiropractic techniques can often be used to treat these common maladies.
A day in the life
The average dental professional spends most of the day delivering dental care in a seated position, bent slightly at the waist, neck tipped downward and arms held at a 90-degree angle. It is easy to see how adopting this position for extended periods day after day can lead to chronic conditions of physical discomfort for the provider.
The length of the average dental procedure is about 45 minutes to an hour. This includes procedures ranging from placing one or two
composite restorations to completing root canal treatment or a crown preparation. Most general practitioners in a busy private practice will move steadily from one operatory to the next during the day, providing treatments in almost the same position.
Consider the position of the head and neck when delivering dental treatment. In most cases, the head is tilted at about a 45-degree angle from the torso and canted slightly to the left or the right depending on whether the dentist is right- or left-handed (see Photo 1). This posture is the same for a dental hygienist and dental assistant. It’s the only position that allows the provider to clearly visualize the field of treatment. Subsequently, strain is placed on the provider’s neck muscles and cervical vertebrae nearly all day, every day.
Similarly, the arms of the dental professional are stretched from 45 to 90 degrees from the body and held in that position throughout the day. The strain on the musculature of the shoulder and neck will certainly at some point create discomfort in those areas as well.
And finally, the most troublesome areas for most dental professionals are the hips and low back (see Photos 2 and 3). While the smart dentist will focus on maintaining good vertical posture to minimize strain on these areas, it is impossible to avoid this awkward, unnatural position completely.
The chiropractor’s perspective
If you have a large number of patients who are dentists and dental hygienists, you’ll see these patients tend to present with the same patterns and mechanisms of injury. How these clinicians hold their posture throughout the day correlates with their chronic muscular conditions.
Consider how their repetitive postures affect their biomechanics.
If you were to rest your elbow on a table and hold a hammer vertically above your forearm, your entire forearm would eventually become fatigued. Consequently, if you bend your wrist and hold the hammer slightly forward you will notice the muscles in the posterior of your forearm becoming fatigued quicker than the muscle of the anterior forearm.
This is because you moved the hammer outside of your forearm’s center of gravity thus forcing the muscles on the posterior of your forearm to work harder to keep the hammer vertical. If you relate this scenario to the muscles of your neck, you can create a simple comparison for the muscular pain a dentist finds after years of practice.
When a dentist’s head is tilted 45 degrees from the torso, the stress on the posterior muscles of the neck is increased due to the head being moved outside of the body’s center of gravity (see Photo 1). Once the posterior muscles become fatigued, they begin to spasm creating tightening or loss of elasticity of the muscles themselves.
After extended periods of the dentist holding his head in this position, the muscles tend to deplete themselves of oxygen and increase the buildup of waste, resulting in chronic pain. Along with the posterior muscles becoming fatigued, the anterior muscles have a tendency to become contracted and over- developed on the rotated side when the dentist is looking at the patient. In a study on this subject, dentists reported 26 to 73 percent prevalence of neck symptoms over the previous year, and dental hygienists reported even higher rates, from 54 to 83 percent for neck symptoms.1
Pain in the neck
A common complaint among dentists and dental hygienists is neck pain with headaches that start halfway through the workday. This complaint is usually directly related to static posture and tightening posterior muscles that cause the occiput to move posteriorly over C1. A manipulative realignment of the cervical region typically results in relief of pain and immediate increased range of motion.
In the adult version of torticollis, a painful spasm of the sternoclei- domastoid (SCM) muscle causes the head to be held in rotation and sometimes slight flexion. (Figure 1). In pseudo-torticollis, there is an inability to move the head in any direction without pain.2 This can easily be caused when the dentist’s head is positioned in a flexed and rotated position for extended periods. Pseudo-torticollis can be successfully treated with as little as six treatments over three weeks.
Lower back pain
As a dentist sits in the rotated and slightly forward position, the lumbar erector spinae muscles are fully engaged. In another study, researchers sought to determine the prevalence of back pain among dentists and its possible correlation with working posture. The study was conducted among 60 dentists and showed a 70 percent incidence of back pain among the population under review.3
Just as the office worker notices pain after years of sitting, the dentist is no exception. The dentist, however, seems to sit in a more erect angled position that creates more pressure on the lumbar spinal joints. Sitting causes a reduction in lumbar lordosis and sacral slope compared with standing, which might cause a spinopelvic imbalance and result in chronic low-back pain.4
Treatment options
In most cases, treatment consists of chiropractic manipulation and physical therapy to create fluid motion between the vertebral joints and restore elasticity in the chronically tight cervical musculature. Because of the elasticity in the muscles of younger patients, there is a significantly higher prognosis of improvement. Elderly dentists, conversely, may have degenerative factors of the spine complicating their recovery and an X-ray should be taken to assess their condition.
Electrical muscle stimulation and ultrasound can reduce inflammation and increase blood flow to the injured musculature, tendons and ligaments. In fact, thermal ultrasound over latent trigger points is comfortable and can decrease the stiffness of a trigger point.5 Also, ultrasound and heat are effective in reducing myofascial trigger points in muscles.6
Passive gentle stretching, proprioceptive neuromuscular facilitation (PNF) stretches and massage can also reduce muscle stiffness and promote elasticity of tightened muscles. Performing a stretching and strengthening program consisting of cervical stretches that can be performed between patient treatments throughout the day can enable dental professionals to reduce muscle tightening.
Stretches that focus on the SCM muscles can be beneficial to relieving spastic muscles of the neck. Strengthened posterior neck muscles allow the dentist to hold static positions for longer periods. Along with lower back stretches, the chiropractor should emphasize the importance of core strength to enable the dentist to sit in working positions for extended periods.
Lumbar support braces, such as sacroiliac belts, can provide additional support during the workday. These belts act as a secondary support system and relieve muscle tension and pain in the lumbar spine. As the dentist strengthens core muscles through a prescribed exercise program, the support brace can be worn less.
When muscles become chronically tight, there is a restriction of vertebral movement and concomitant reduced range of motion. Clinicians should consider utilizing thrust manipultive procedures to reduce pain and disability in patients with mobility deficits and acute low back and back-related buttock or thigh pain.7
Jeffrey Bentz , DC, is a graduate of Palmer College of Chiropractic and practices in a multi-doctor corporation in Pittsburgh. He works directly with family physicians, orthopedists and neurosurgeons.
Robert Agostino, EdD, recently retired as a professor in the School of Education at Duquesne University. He works on chiropractic educational ideas for professional growth with the chiropractic community.
Joseph Smith, DDS
References
1 Morse T, Bruneau H, Dussetschleger J. Musculoskeletal disorders of the neck and shoulder in the dental professions. Work. 2010;35(4):419-29.
2 Souza T. (2005). Differential Diagnosis and Management for the Chiropractor. (Pg 71). Burlington, MA: Jones and Bartlett Learning, Inc.
3 Gaowgzeh R, Chevidikunnan MF, Saif AA, et al. Prevalence of and risk factors for low back pain among dentists. Journal of Physical Therapy Science. 2015;27(9):2803-2806.
4 Cho IY, Park SY, Park JH, et al. The Effect of Standing and Different Sitting Positions on Lumbar Lordosis: Radiographic Study of 30 Healthy Volunteers. Asian Spine Journal.2015;9(5):762-769.
5 Draper DO, Mahaffey C, Kaiser D, Eggett D, Jarmin J. Thermal ultrasound decreases tissue stiffness of trigger points in upper trapezius muscles. Physiotherapy Theory and Practice. 2010;26(3):167-72.
6 Benjaboonyanupap D, Paungmali A, Pirunsan U. Effect of Therapeutic Sequence of Hot Pack and Ultrasound on Physiological Response Over Trigger Point of Upper Trapezius. Asian Journal of Sports Medicine. 2015;6(3):e23806.
7 Delitto A, George SZ, Dillen LV, et al. Clinical Practice Guidelines Linked to the International Classification of Functioning, Disability, and Health from the Orthopaedic Section of the American Physical Therapy Association.Journal of Orthopaedic & Sports Physical Therapy. 2012;42(4).
