The purpose of this study is to show the different diagnostic and therapeutic method for correction of deep-bite and open-bite skeletal class III malocclusions. This study utilized two experimental groups: the former included 16 skeletal deep-bite patients: 13 treated only by interceptive orthodontics, and 3 undergone to orthognatic surgery; the latter consisted of 21 skeletal open-bite patients: 5 treated only orthodontically , 16 undergone to a surgical-orthodontic treatment. The treatment consists in the interceptive orthodontics in skeletal deep-bite malocclusion in the active period of the growth . In skeletal open-bite malocclusions the approach consists in presurgical-orthodontic preparation, orthognatic surgery, final orthodontic correction. In both groups and excellent aesthetic, dental, skeletal, neuromuscular results were obtained. In the other open-bite patients the functional result was not satisfactory. The therapeutic approach of open-bite malocclusions must begin at the end of growth by three dimensional, surgical orthodontic treatment on both the jaw-bones.