بررسی تغییرات قوس های دندانی بیماران متعاقب استفاده از دستگاه اکسپنشن Y شکل

The purpose of this study was to evaluate Y shape appliance for expansion on maxillary arch of patients in their mixed dentition age. Eight patients, 6 girls and 2 boys, with maxillary constriction, retrusion of maxillary anteriors, and space deficiency of upper canine were treated by Y-plate expansion. For each patient 8 parameters on upper cast and 7 parameters on lower cast were measured. Statistical analysis was conducted by calculating the mean, standard deviation and p-value, of parameters. Since these parameters change during natural growth, the results were compared to normal growth changes of similar patients group form another study as control. Results showed significant increase in maxillary and mandibular cervical and coronal intercanine and intermolar width (P<0.005). The results also showed significant increase in maxillary arch length and perimeter.