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Published on: February 23, 2024
Evaluation of the effect of trimline types of clear aligners on esthetic perception using eye-tracking technology and
Merve Kurnaz1, Nuray Akbıyık Bayam1, Semir Öztürk1
1From the Department of Orthodontics, Faculty of Dentistry, Istanbul Kent University, Istanbul, Turkey.
Introduction:
This study aimed to compare the impact of clear aligners with different edge finishes on esthetic perception across various specialties, using eye-tracking technology and the visual analog scale.
Methods:
Three different trimlines are designed at the gingival border: short scallop, straight, and straight extended. The designed aligners were taken in the mouth without a retractor, in a dark environment with a softbox. The prepared images were turned into a survey via the Google Docs document service. The survey questioning esthetic success according to a 5-point Likert scale was sent to the participants via the online channel. Eye tracking will also take place online with Sticky (version 1.4, Tobii Pro Lab; Tobii Technology AB, Danderyd, Sweden), the online form of the Tobii X2-60 eye-tracking software. The data obtained in this study were analyzed using the SPSS software (version 22; IBM, Armonk, NY). Mann-Whitney U test and Kruskal-Wallis H test with Bonferroni correction were used.
Results:
No significant difference was observed among the specialties in terms of scores (P >0.05). In both male and female subjects, all surfaces showed significant differences across trimlines for the number of fixations, number of visits, and time viewed. In addition, Region 2 exhibited significant differences in the number of fixations, number of visits, and time until noticed (P <0.05). In males, region 3 showed significant differences across trimlines for the number of fixations, number of visits, and time viewed (P <0.05). In females, time until noticed also differed significantly (P <0.05). In both male and female subjects, region 4 showed significant differences across trimlines for the number of fixations, number of visits, and time viewed (P <0.05).
Conclusions:
No differences were found among the specialty groups using the conventional survey method. Scalloped and straight trimlines were generally noticed.

