Self-ligating vs Conventional Brackets and Labial Bone Thickness During Crowding Correction in Adults

This randomized clinical trial compares two types of orthodontic brackets, self-ligating and conventional, in adults aged 18 to 25 with moderate crowding of the lower front teeth (4 to 8 mm). The main question is whether the type of bracket affects the thickness of the thin bone covering the front surface of the lower incisor roots (labial alveolar bone) during the leveling and alignment phase of treatment. Some clinicians claim that self-ligating brackets with light-force copper-nickel-titanium wires let the bone adapt and follow the teeth, while others report bone thinning with both systems. Twenty participants will be randomly assigned to self-ligating or conventional brackets. Bone thickness will be measured on cone beam computed tomography (CBCT) scans taken before treatment and at the end of leveling and alignment. The study will also compare the speed of alignment, changes in tooth inclination (torque and tip), pain, root resorption, and periodontal health between the two groups.

Inclusion Criteria: * Adults aged 18 to 25 years with a full set of permanent teeth * Moderate lower anterior crowding (4 to 8 mm) * Angle Class I malocclusion with skeletal Class I relationship Exclusion Criteria: * Medically compromised patients * Skeletal discrepancies * Periodontal problems * Need for extraction as part of orthodontic treatment * Patients taking medications * Parafunctional habits (bruxism, tongue thrusting, mouth breathing) * Nickel allergy * Impacted lower teeth