Evaluation of the effectiveness of different retention apliances used after orthodontic treatment with digital modelling method

Aim: The aim of this study is to evaluate the effect of different retention apliances on the success of treatment in individuals with differently planned orthodontic treatments. Material and method: This study was carried out in 72 patients who were treated in the Orthodontics Department of Dentistry Faculty of Inönü University. Research groups were identified as 1st Group, nonextraction-Essix; 2nd Group, extraction-Essix; 3rd Group nonextraction-SP; 4th Group, extraction-SP; 5th Group, nonextraction-Hawley; 6th Group extraction-Hawley. Digital model records are 5 as head of treatment (T0), end of treatment (T1), 3rd months of retention (T2), 6th months of retention (T3) and 12th months of retention (T4). Results: No significant differences were found in overjet, overbite, intercanine and first intermolar width and arch depth among the subgroups in the upper and lower jaws measurements on the digital models in the T0, T1, T2, T3 and T4 periods (p>0,05). In the individuals treated with extraction and nonextraction, intercanine distance was increased by treatment and protected during the retention period. In the individuals treated with extraction, first intermolar distance and arch depth were lower than the individuals treated nonextraction. In 3rd Group, the lower incisors crowding was statistically significantly lower than 1st Group and 5th Group in T4 period. There is no statistical difference in incisors crowding between the retention appliances in the individuals treated with extraction. Conclusion: For nonextraction orthodontic treatments, SP is recommended especially for the lower incisors for incisor stability. There is no difference in incisor stabilization in the use of Essix, SP and Hawley in extraction treatments.