Peculiarities in the orthodontic treatment of dental crowding associated with arch compression

Abstract

Introduction. Decreased transverse and sagital length of dental arches are characteristic signs of patients with dental crowding. This is to conclude that one of the orthodontic treatment aims is to expand dental arches. Objective of the study. Increase the diagnosis efficiency and simplify the treatment methods of DDA with crowding by using dental arches expansion. Study goals. 1.Selection of appropriate and efficient methods in dental crowding diagnosis. 2. Study the efficiency of rigid arches usage in the treatment of dental arch compression associated with crowding. 3. Ensure the treatment result stability of this pathology by applying more effective retention methods. Methods and Materials. This study is based on the evaluation of 22 patients with dental crowding, in which the expansion of the transverse and sagittal lengh of dental arches was performed. 6(27.3%) were male, 16(72.7%) - female. The average age of the patients was 15.86±1.25 years. Diagnosis was established based on clinical examination, X-ray examination (lateral cephalometrics and panoramic X-ray, cone beam computed tomography), biometric study of the casts (Pont, Korkhaus, Bolton analysis). In all patients,during the orthodontic treatment, were used fixed MBT appliances with a .022″ slot in combination with a dental arch expansion device. Results. According to the facial type, the patients were divided into:13(68.42%) cases – euriprosop type, 3(15.79%) cases – mesoprosop type, 3(15.79%) cases – leptoroprosop facial type. The SI index was 31.85 mm±0.37. There were 18(72.0%) patients with normodentia, with macrodentia - 7(28.0%). The anterior Bolton indices had a value of 77.88%, 0.68% higher than the norm. The intermolar width of the upper dental arch, before treatment, was reduced with 4.77 mm, the lower one with 3.51 mm. When analyzing the total space in the lower arch, a total deficit of 8.04 mm was detected. The duration of the treatment by expansion of the dental arches was 16.82 months ± 0.78, being truthfully shorter than in cases with extractions (p<0.05). Conclusions. In the diagnosis of dento-alveolar disharmonies with crowding is important the use of total space analysis in association with cephalometric analysis. To simplify the treatment, it is necessary to use in several patients the possibility of expanding the arches by activating the rigid stainless steel wires. To ensure the stability of the treatment result and to preserve the created transverse width, the use of retention appliances made of rigid plates with a thickness of 1.5 mm can be recommended.