Bracket Positioning Techniques and Quality of Orthodontic Finishing

This three-arm randomized clinical trial compares three orthodontic bracket positioning techniques - Smile Arc Protection (SAP), Smile Arc and Marginal Ridge Approach (SAMRA), and the McLaughlin-Bennett-Trevisi (MBT) bracket placement chart (control) - in young patients with Angle Class I malocclusion and mild-to-moderate crowding treated non-extraction. The primary aim is to determine which technique yields the highest quality of orthodontic finishing, measured with the American Board of Orthodontics Objective Grading System (ABO-OGS). Secondary aims compare anterior tooth tip and torque (assessed by CBCT) and mini-esthetic smile parameters (gingival display, incisal display, buccal corridor, and smile arc, assessed on standardized posed-smile photographs) among the three techniques.

Inclusion Criteria: 1. Males and females aged 14-25 years with a full permanent dentition. 2. Mild to moderate crowding requiring non-extraction orthodontic treatment (2-6 mm per Graber's classification). 3. Angle Class I malocclusion. 4. Normal skeletal vertical dimension (SN-MP angle 32° ± 5°). Exclusion Criteria: * 1\. Medication that may cause gingival inflammation (e.g., cyclosporine, phenytoin). 2\. Impacted, extracted, or missing permanent teeth (except third molars). 3. Periodontal disease or parafunctional habits (bruxism, tongue thrusting, mouth breathing). 4\. History of previous orthodontic treatment. 5. Craniofacial anomalies, facial asymmetry, or skeletal discrepancy.