sentences:  His increasing interest in dental occlusion and in the treatment necessary to obtain normal occlusion led directly to his development of orthodontics as a specialty, with himself as the "father of modern orthodontics".The development of Angle's classification of malocclusion in the 1890s was an important step in the development of orthodontics because it not only subdivided major types
  of malocclusion but also included the first clear and simple definition of normal occlusion in the natural dentition.Angle was concerned with the aesthetics of orthodontics as well as functionality and so he collaborated with the artist and art educator Edmund H. Wuerpel in applying aesthetics to his field.