Parents of an 8-year-old child have made and appointment with an orthodontist. There are complaints of their child having traumas of oral mucosa. Objectively: decreased height of the lower face, everted lower lip, deep labiomental furrow, milk occlusion. The upper incisors fully cover the lower ones; cutting surface of the lower incisors make contact with the anterior third of the palate. Mesiodistal ratio of the canines and the first permanent molars is normal. Grouping of the upper and lower front teeth is dissimilar. Make the diagnosis according to the Kalvelis classification: