Posture hazards in the dental practice

Many multi centre worldwide studies show that over 65%over Dental Health Care workers suffer from Musculo Skeletal Disorders sometime in their working careers, causing pain and discomfort whilst working, time off from the surgery and indeed many have to retire early.

The European Society of Dental Ergonomics has tried to address the issue but there does seem a lack of want to change on behalf of the profession.

For the patient a dental visit typically involves sitting in a reclined or even supine position and the dentist has to contort his body to perform the oral work. We also use a variety of hand tools in a delicate manner.

Most of us know we sit in poor ergonomic positions for much of our working life but fail to respond to the symptoms and think it is just part of the job. The younger ones amongst you feel it only happens to the older ones instead of ensuring prevention now. You are not immortal!!

During working, a dentist maintains varying positions for prolonged periods of time, and one can only speculate on the amount of load and stress suffered by the Cervical andLumbar spine.

Over time, these awkward postures of forward bending and repeated rotation of the head neck and trunk to one side lead the muscles responsible to become stronger and shorter whilst opposing muscles become weaker and elongated.

The ESDE suggested conditions for obtaining an optimal working posture are

Sit in a stable upright working posture.

Place the working field in the mouth straight before the upper body in the symmetrical plane

Look as much as possible, perpendicularly upon the working field.

Sit as far back as possible in the seat to obtain a stable posture, symmetrically upright.

Arms tucked in to the upper body to support the arms whilst carrying out treatment.

Angle between lower and upper legs of about 110° or a little more, with the legs slightly spread.

Working height adjusted properly, with the lower arms lifted a little from about 10° to a maximum of 25°.

Distance between working field in the mouth and eyes or spectacles normally between 35 –40 cm.

The back must be supported at the upper/backside of the pelvis so that as soon as the muscles become too fatigued to maintain an upright position of the back, the back-rest ensures that the desired upright posture can be maintained.

Instruments are handled with the modified pen grip: withthe first 3 finger bent in a round form around the instrument and the last 2 fingers resting on a firm basis inor outside

You may compare the position of the working field in the mouth of the patient with the position in which you hold an apple when peeling it or a needle when preparing to thread it: you will hold these straight before your upper body without bending your head.

Further the oblique position you hold your book or Kindle when sitting in a chair to read (with the lamp besides/behind you) gives you an impression of how to place the working field so as to be able to look about perpendicularly upon it. By turning the head of the patient within the three planes it is possible to place the working field in a position to allow the image of the tooth you are working on to come straight into your eyes.

If this does not happen the eyeballs steer the head until itreaches this position and then the body posture changes automatically. In this way the eyeballs come into the position of looking perpendicularly upon the working field as much as possible.

In order to support the horizontally positioned bottom and the obliquely sloping down thighs equally, when sitting with an angle of 110° between upper and lower legs, the rear 20 cm of the seat should run horizontally and the front 20 cm downward with an angle of 20°. This is the Balanced Home Posture position.