The mechanical testing and performance analysis of three-dimensionally produced lingual retainers

Background: Introducing three-dimensional (3D) printing has opened new visions in the orthodontic field. This research evaluates three-dimensionally produced orthodontic retainers and their future possible uses. For this purpose, in vitro tests were performed for these groups, including bond strength, failure analysis, discoloration, and biodegradation. Methods: A total of 30 specimens (n = 30), lower incisor human teeth, were randomly divided into three groups for a bond strength failure analysis (for each group n = 10). In the experimental groups, lingual retainers were fabricated using 3D systems (group 1 with 3D dental pen and group 2 with 3D-printed). In the control group (group 3), the retainer system was a combination of a wire and composite, which is being used worldwide. A total of 30 specimens (n = 30) from the 3D dental pen and 3D-printed for discoloration and biodegradation tests were divided into three groups (water, tea, and coffee). Data were analyzed using the Mann-Whitney U test, ANOVA, and chi-square test. Results: For all parameters tested, significant differences were determined among groups. The 3D pen group had the highest score for bond strength, whereas discoloration differed significantly. Conclusions: According to the limitations of this research, 3D-printed retainers have the potential for clinical use in the near future.