3-Dimensional topographic enamel surface changes after different debonding techniques for aligner attachments: a micro-CT study.

Introduction: To evaluate topographic changes of enamel surface in 3-dimensional after different debonding methods of aligner attachments formed with 2 different composite resins.

Methods: Vertical rectangular attachments were created on 88 premolar teeth and divided into two composite resin groups (Group 1:flowable, Group 2:packable) (N = 44). These were then divided into two subgroups (N = 22) using different debonding methods. In Group A, the attachments were firstly removed using an attachment debonding plier and then with white fiberglass. Following, the tooth surfaces were polished with blue fiberglass. In Group B, the excess attachment composite was removed with a 12-blade carbide bur, followed by a 24-blade carbide bur, and tooth surfaces were polished with Renew stone. The remaining composite volume was measured using Geomagic Control X software. Enamel surface roughness and morphological change were compared between the groups.

Results: Residual composite resin volume did not show a statistically significant difference between composite resin groups (1-2 A). The enamel demineralization volume and area changes in Group 2 A were significantly higher than observed in 2B (p < 0.05). Roughness parameters Ra (T1-T0), Ra (T2-T0), Rq (T1-T0), and Sa (T1-T0) were significantly higher in Group 1B compared to Group 1 A (p < 0.05). Similarly, Ra (T1-T0), Sa (T1-T0), and Sq (T1-T0) parameters were significantly higher in Group 2B compared to Group 2 A (p < 0.05).

Conclusions: Fiberglass with a debonding plier produced a smoother enamel surface compared to carbide burs, but caused significantly more enamel demineralization, as seen in micro-CT evaluations after polishing.