Orthodontic Bracket Bonding

Participants for this study will be recruited from the Department of Orthodontics at National Taiwan University Hospital (NTUH). Given that younger children may have incomplete tooth eruption, short clinical crowns, and challenges with behavioral control, this study will include only patients aged 20 and older. Eligible participants will be those undergoing comprehensive, non-extraction orthodontic treatment with complete dentition (excluding wisdom teeth) and thorough documentation, including panoramic and lateral cephalometric radiographs, models, and intraoral scans. For eligible patients, informed consent will be obtained prior to treatment, and they will be randomized into different groups to receive bracket bonding using various techniques according to the randomization protocol. Random assignment will be block-stratified and conducted with assistance from an independent statistician, with expert oversight ensuring all patients are correctly allocated.

All first-year orthodontic residents at NTUH will participate in this study as bracket positioning is a fundamental component of their orthodontic training. These residents will receive lectures on traditional direct bonding procedures and hands-on training in digital orthodontic techniques, supported by standard operating procedure manuals for each bonding technique. As all procedures align with standard clinical practice, no additional patient risks or protective measures are needed.

For patients who have undergone virtual bonding before actual bonding, an intraoral scan will be taken post-bonding to assess differences between planned and actual bracket placement. All participants will adhere to a treatment schedule with appointments every three to four weeks, advancing according to the supervising orthodontist's evaluations. Upon treatment completion, documentation will include panoramic and lateral cephalometric radiographs, impressions, intraoral scans, and retainer fabrication.

Statistical analysis will be conducted using SPSS (Version 20; IBM Corp., Armonk, NY, USA). The study will assess the accuracy of bracket placement and evaluate correlations between pre-treatment occlusion and post-treatment outcomes across different bonding techniques.

Inclusion criteria

i. Patients with a fully erupted permanent dentition. ii. Orthodontic treatment plans that do not require extractions (excluding wisdom teeth).

iii. Patients who have not previously undergone orthodontic treatment. iv. Complete dentition (excluding wisdom teeth). v. Adult patients aged 20 years or older.

Exclusion criteria

i. Patients requiring extraction of teeth other than wisdom teeth. ii. Fixed prostheses on teeth other than molars. iii. Significant tooth morphology defects requiring fixed prosthetic restorations.

iv. Missing teeth (excluding wisdom teeth). v. Patients with fractured crowns or large restorations on the buccal surfaces of crowns.

vi. Teeth with severe rotation or crowding that may impede direct bonding or tray placement.