In the last years prevention of temporomandiboular joint (TMJ) disease had acquired great importance. According to the neuro-occlusal rehabilitation (RNO) it is possible to say that TMJ disease starts since first years of life. So it is important both for dentist and for pediatric know what are the conditions and the atypical functions which predispose to this pathology. The aim of this work was to show how it is possible to intercept since primary teeth and the correct norms of primary and secondary prevention.