Are you planning to make upgrades to the chairs in your dental operatory but are wondering where to start? My advice is to think ergonomically and practically. Is it necessary to replace all of the chairs? Or should you replace one at a time as needed? Some key ergonomic questions can help you decide.
The patient chair
The goal is the getting to the oral cavity. A thick, padded back can limit the dentist’s ability to comfortably place his or her legs under the chair. A wide back rest can limit easy access to the oral cavity and the ability to maintain a proper, balanced working posture. The path of least resistance requires that the patient chair be thin and narrow behind the patient’s head. Patient comfort is important but not at the risk of limiting the dentist’s access to the oral cavity. An adjustable head and neck support for the patient will allow him or her to be properly supported and positioned for procedures. Lastly, can the chair be easily adjusted from left- to right-handed? When choosing a chair, ask yourself, can I maintain good, balanced posture when treating a patient?
The operator stool
The operator stool should be infinitely adjustable to provide the dentist with support and comfort while in a balanced working posture. The seat should adjust up and down, as well as tilt slightly forward to allow the dentist’s hips to be slightly higher than his or her knees. This position will place the pelvis into an anterior tilt facilitating a balanced position of the spine.
The height of the hydraulic cylinder should also allow the dentist to assume this position. Taller people should consider a taller cylinder. When in doubt, ask your vendor for a trial period to ensure you have a cylinder that is the appropriate height. The back of the operator chair should adjust up and down as well as anteriorly and posteriorly. The adjustability of the back should provide support for the dentist while in a balanced sitting position.
Another option to consider is a version of the saddle seat, which is available from a number of manufacturers. The saddle seat allows for a range of heights that lets the dentist move from sitting to a semi-standing position. Generally there are three types: standard, which is more like a motorcycle seat; the English riding saddle version, and the newer split saddle. Although all of these offer differing features, the ultimate choice is quite individual, and I would strongly recommend using a stool for a trial period before buying it for a number of anatomic reasons. Remember, there is no “one size fits all.” The saddle seat is a bit of an acquired taste, and it is absolutely necessary to try it before you buy it.
There are a number of options for armrests. Many practitioners have spent their entire careers working without their arms supported. Research published in the Journal of the California Dental Association showed that dental practitioners spend nearly half of their working day in poor seated postures. Specifically, forward head with rounded shoulders, elevated arms, kyphotic upper backs and a flexed lumbar spine.
The infamous “chicken wing” position becomes the working “norm.”
Poor working postures add additional stress to an already busy day. Arm supports, both built-in or after-market add-ons can be an invaluable stress reducer for the dental practitioner during the working day, adding minutes, hours or even days of comfort for a usually uncomfortable practitioner. Evidence has shown that arm support can facilitate a more appropriate, balanced work position while alleviating stress on the upper quarter of the practitioner. The armrest must comfortably support the upper extremities and should allow 360 degrees of movement. The armrest should not limit the practitioner to a particular plane of movement. Make sure the contour and padding of an armrest does not place undue stress on the neuromuscular structures of the forearm or interfere with the position or movement of the practitioner. Lastly, the armrests should be able to be easily moved out of the way not needed.
The assistant stool should possess similar characteristics to the operator stool to provide support and comfort. With regard to the “belly bar,” it’s time to move away from it to a better balance position. The belly bar tends to obligate the assistant to assume a poor seated position that can limit productivity and, ultimately, career longevity. Usually, the root of the problem with this poor position is the operator’s insistence on strictly using direct visualization along with the dentist putting his or her head in the line of sight of the assistant. A number of assistant programs have instituted use of a saddle seat which will allow a semi-standing position while being able to get close to the oral cavity. Well-coordinated, four-handed dentistry along with good balanced posture will allow the assistant to assume a better-balanced seated position.
There are a number of clinicians who have chosen a more out-of-the-box seating system, namely the ball. Although it may seem that sitting on a ball to perform dental procedures may be inherently too unstable, there are a fair number of clinicians who have chosen this approach — a workout while sitting to work approach. There is a small learning curve to get it tuned in and this may include a fall or two. This approach engages your core and postural muscles while you work. The shortcomings are lack of adjustability in height, particularly if one shares the chair with a much taller or shorter colleague and the inability for dental assistant to use it effectively.
Mr. Caruso is a practicing physical therapist with 30 years of experience. He has worked extensively with the dental profession in ergonomics, injury prevention, productivity, exercise and wellness and is a member of the ADA Dental Wellness Advisory Committee. He is president and cofounder of the Kids Equipment Network, a not-for-profit organization that has provided over 2,000 children with special needs adaptive equipment at no cost. Contact him at firstname.lastname@example.org.