What causes scoliosis?
Let’s take the example of a lack of dental height on the left maxillary arch. In this case the skull, according to simple physical and biomechanical principles, tends to sink down at just that point.
During this act of sinking the skull changes its inclination in regard to the jaw. As a result the left masseter muscle becomes shorter and stronger than the right one, which on the other hand becomes longer.
This forces the upper and lower jaws into contact on the left side, where there is a lack of dental height. In fact, the skull falls for two reasons: the force of gravity and the muscular tension in the masseter muscles. In effect it would be more correct to say that the masseter muscles force the teeth into occlusion until they recreate enough pressure within the upper and lower teeth to support the skull.
This pressure, according to the Second Law of Newton, is called the “reacting force”. Thus, as we have seen, the masseter and temporal muscles on the left side become shorter. As a result the masseter and temporal muscles on the right become longer.
The immediate consequence of this is a displacement of the skull towards the left shoulder, precisely because the muscles on the left side have become shorter. After that the muscles on the left side pull the left shoulder towards them.
This happens due to the fact that these muscles are shorter and therefore much stronger as well. The rise of the left shoulder pulls in turn the left occipital muscle, the left trapezius muscle, the left dorsal muscle and the left posterior serratus muscles towards itself.
This process takes place in such a way that the spine is twisted. It is this phenomenon that causes scoliosis. It does seem incredible that such a muscular deformation can have its roots in a simple lack of dental height.