Researchers from Tokyo Medical and Dental University (TMDU) have found that cartilage growth in newborn rat jaws is inhibited in a group of animals exposed to intermittent hypoxia, or periods of low oxygen. They observed a thinner layer of cartilage in the jaws, but not in the tibias of the rats. These interesting results show how various cartilage throughout the body differs, as well as the importance of oxygen in proper jaw cartilage growth and development.