First-class devices with a shape suitable for a cranial conformation in extension and, therefore, with ogival arches. The devices are indicated for an orthopedic functional action, in different types of malocclusion, when discrepancies of the dental skeletal bases are found, when there are imbalances of the axes of eruption of the teeth, in the dysmorphosis in the vertical sense, in the lateral deviations, in the inclined occlusal planes that are not horizontal.