Evaluation of the effects of different fixed lingual retainer materials on post treatment stability

The aim of this study is to evaluate the effects of different lingual retainers on the stability and periodontal health of the mandibular anterior teeth. A total of 140 patients who received non-extraction orthodontic treatment were included in the study. In group 1, 0.0175 inch 7-stranded stainless steel retainer wire, in group 2, 0.022 x 0.016 inch 8-wire dead-soft retainer wire, in Group 3, 0.038 × 0.016 inch prefabricated stainless steel wire, and in Group 4, fiber reinforced composite retainer wire were used. Digital models of the patients were obtained before the treatment, at the end of the treatment, 3 months, 6 months, 9 months and 12 months after the treatment. Measurements that evaluate stability such as Little's irregularity index, intercanine distance and arch length were performed. Connection failures and breaks in the wires were evaluated. Plaque index, gingival index and calculus index were used to evaluate the health of periodontal tissues.Little irregularity index increased significantly in all groups. Intercanine distance decreased significantly in all groups except Group 1 and arch length in all groups. After one year, the change in Little irregularity index was found to be significantly higher in Group 2 and Group 4 than in Group 1 and Group 3. Intercanine distance changes decreased significantly more in Group 2 and Group 4 than in Group 1 and Group 3. There was no significant difference in arc length changes between the groups. At the end of one year, fractures in the retainer wires were observed significantly more in Group 4 than in the other groups. Connection failures (detachment from the adhesive) were significantly higher in Group 2 than in the other groups. Plaque index, gingival index and calculus index increased significantly in all groups. At the end of one year, there was no difference between the groups in plaque index , gingival index and calculus index changes.According to the findings of the study, it was recommended to use 0.0175 inch 7-stranded stainless steel retainer wire and 0.038 × 0.016 inch prefabricated stainless steel wire of lingual retainer.