A dental stool with chest support reduces lower back muscle activation

Activation of back musculature during work tasks leads to fatigue and potential injury. This is especially prevalent in dentists who perform much of their work from a seated position. We examined the use of an ergonomic dental stool with mid-sternum chest support for reducing lower back muscle activation. Electromyography of lower back extensors was assessed from 30 dental students for 20s during three conditions in random order: (a) sitting upright at 90 degrees of hip flexion on a standard stool, (b) leaning forward at 80 degrees of hip flexion on a standard stool, and (c) leaning forward at 80 degrees of hip flexion while sitting on an ergonomic stool. Muscular activity of the back extensors was reduced when using the ergonomic stool compared to the standard stool, by 33-50% (p<0.01). This suggests a potential musculoskeletal benefit with use of a dental stool with mid-sternum chest support.