Accuracy comparison of orthodontic movements obtained with 3D printed and thermoformed aligners: a retrospective cohort study.

AIMS: The aim of this retrospective cohort study is to calculate the accuracy of dental movement in consecutively treated patients treated with thermoformed and direct printed aligners.

METHODOLOGY: Two patient groups were included in the analysis. The first group consisted of 34 consecutively treated patients (23 females, 11 males; mean age 26.3 ± 13.7 years; age range 9-63), who were treated using 3D-printed aligners and a second group included 40 consecutively treated patients (28 females, 12 males; mean age 27.5 ± 12.5 years; age range 12-57), who received treatment with thermoformed aligners made of polyethylene terephthalate glycol (PETG). Digital analysis were performed to evaluate for every tooth torque, tip and rotational movements for each tooth as well as accuracy of planned movement. (Delta-Dent software, Outside Format, Milano, Italy) as well as accuracy of planned movement. The differences between groups in the toothwise movement accuracy were tested using the Mann-Whitney U test The Kruskall-Wallis test was used to evaluate the difference among teeth values. The differences were considered statistically significant at P < 0.05.

RESULTS

1018 teeth were measured. The overall accuracy of the torque was 60% for the DPA group and 66% for the TFA group; was 52% for the DPA group and 61% for the TFA group for the tip and the overall accuracy for rotations was 58% for the DPA group and 69% for the TFA group; none of the differences resulted statistically significant.

CONCLUSIONS

All treatments were successfully completed with similar amounts of refinement stages. No statistically significant differences were found between the two groups in respect of rotation, tip and torque movements.