Comprehensive clinical evaluation of indirect and direct bonding techniques in orthodontic treatment: a single-centre, open-label, quasi-randomized controlled clinical trial.

Background: Few prospective investigations have compared direct and indirect techniques through comprehensive and detailed clinical evaluations, considering the impact of all factors.

Objectives: This study aimed to compare and evaluate direct and indirect bonding methods at a single institution and to clarify the selection criteria for the bonding method.

Materials and methods: This single-centre, quasi-randomized controlled clinical trial included 153 patients who required fixed orthodontic treatment. They were randomly divided into indirect and direct binding groups by the project lead (K.K.), who was blinded to all clinical data, and performed the allocation using medical record numbers. The chair time for bracket bonding, discomfort during bracket bonding, oral hygiene after bonding, number of bracket failures, number of intentional bracket reattachments, post-treatment occlusal index, and total treatment time were assessed. Outcomes were compared using a two-sample t-test or Mann-Whitney U test (P < .05).

Results: Fifty-eight patients were included in the indirect bonding group (20 male, 38 female; mean age: 20.63 ± 5.69 years) and 66 (14 male, 52 female; mean age: 23.17 ± 8.83 years) in the direct bonding group. Compared to the direct bonding group, the indirect bonding group had shorter chair time (P < .001), a shorter total treatment period (P < .01), and a better final occlusal relationship (P < .001). The number of bracket detachments was higher (P < .001) in the indirect bonding group, but the number of intentional reattachments was lower (P < .001).

Conclusion: Indirect bonding may improve the efficiency of orthodontic treatment.

Harms: No harm was observed during the study.

Trial registration number: This trial was approved by the Ethics Review Committee of Okayama University (approval number: d10001), UMIN registration number 000022182.