Assessment of bone thickness in the areas where mini screw assisted rapid palatal expansion appli̇ances will be placed according to different growth types by cone beam computed tomography

Objective: It was aimed to evaluate the bone thickness in areas where miniscrew supported rapid palatal expansion appliance (MARPE) will be placed according to different growth types, using cone beam computed tomography (CBCT). Materials and Methods: Radiographs were randomly selected from the CBCT archive according to the inclusion criteria. Cephalometric radiographs were analyzed digitally and divided into three groups (low, normal and high angle) according to growth patterns (n=34). CBCT scans and measurements were made on both sides, 3 mm and 6 mm lateral to the midpalatal plane. In transversal section, anterior region measurement points were adjusted to pass through the distal of 1stpremolars, and posterior region measurement points were distal of 1stmolars. Measurements were made in sagittal section at 16 points from palatal cortical bone to nasal floor cortical bone at 30-45-90º angles in the anterior region and at 90º angle in the posterior region. Results: The differences were found between growth patterns in terms of palatal bone thickness (p<0.05). The palatal bone thickness of the low-angle group was greater and was significantly higher in measurements made at a 90º angle in the posterior region, 3 mm and 6 mm lateral to the midpalatal plane on both sides. Conclusions: It was thought that palatal bone thickness was affected by many variables such as gender, growth pattern, and insertion angle and showed high individual differences. For this reason, before MARPE device is produced, it may be recommended to prepare the patient by making measurements on CBCT images.