Accuracy of three-dimensional printed guide plate for indirect bracket placement: one-piece verses segmented, an in Vitro study

Abstract

Background: An accurate placement of brackets is a key element of the comprehensive treatment process of orthodontics to achieve an ideal occlusion. Orthodontic brackets can be directly placed on tooth surfaces or indirectly.

Aim: To compare the accuracy of indirect bonding techniques in moderate, and severe crowding cases using three-dimensional printed one-piece transfer tray and segmented trays. Digital models with virtual brackets were considered as the control group. Four points were selected in each tooth to perform the analysis. From the midpoint of each bracket to the mesial margin (CM= center mesial), distal margin (CD =center distal), occlusal/ incisal margin (CI= center Incisal/occlusal) and gingival margin (CG= center gingival). Shapiro-Wilk was used to test the normality of continuous variables. The Mann-Whitney test, Kruskal-Wallis H test was used. A P-value of less than 0.05 will be considered significant in all statistical analyses.

Results: There were statistically significant differences between models with moderate crowding bonded using full, segmented transfer trays and control for CD12, CD21, CI25 (P < 0.001). While the rest of the measurements showed no significant differences between models with moderate and severe crowding bonded using full, segmented transfer trays and control (P=1.0).

Conclusion: The one-piece and the segmented indirect 3D printed transfer trays are accurate in the severe and moderate malocclusion.