The most compromised part of the body in the seated dental professional is the lumbar curve. The dental professional most of the time works seated or rotated at the hips. The human adult spine has normally three curves: the cervical (neck), the thoracic (middle back) and the lumbar (lower back). The lumbar curve plays a very important part in keeping the body's balance in an upright position. When working seated, the whole body tilts forward or twists, two situations that apply great pressure on the lower back.