The use of cone beam computed tomography to evaluate of results of the rapid expansion of the hard palate with dental anomalies

The crowding of the permanent incisors with accompanying rotations or anterior cross bite is commonly seen during eruption of the permanent lateral incisors. When crowding is limited to a few millimeters, sufficient space may allow normal growth, but when the upper jaw is narrow and crowding exceeds this amount, rapid expansion of the hard palate may be an effective method. The purpose of this study was to study the method of cone beam computed tomography to evaluate the results of rapid palatal expansion in the narrowing of the upper dentition and the lack of space for incisors and the reaction of intact permanent molars, when fixing the apparatus on primary second molars in the absence of posterior cross bite. The study involved 20 children (age 7-10 years) who were treated with the Haas apparatus. The Haas apparatus was fixed on the upper second primary molars and on the primary canines. Cone beam computed tomography was performed before and after palatal suture rupture. A decrease in incisor crowding was found in all patients. The width between the permanent molars in the diameter has increased significantly, the distance between the tops of the roots of the upper permanent molars has increased more than between the crowns of the teeth. Application of the method shows the possibility of expanding the sky in the transverse direction. The use of a Haas apparatus attached to primary teeth in early mixed dentition in the absence of posterior cross bite is effective and provides a pronounced planned transverse growth of the jaw and can be indicated to expand the anterior part of the upper jaw to eliminate crowding of the upper incisors. With rapid expansion, there are favorable spontaneous changes in the palatal vertical position of the maxillary permanent molars in the opposite direction of expansion and there is the potential to mimic the expected natural transverse growth. Fixation of the apparatus used for this procedure on the primary molars and keeping the permanent molars unused means the prevention of periodontal damage, loss of attachment, demineralization and external resorption of the roots of permanent molars.