Comparison of Three Bracket Positioning Techniques (Smile Arc Protection, Smile Arc and Marginal Ridge Approach, and McLaughlin-Bennett-Trevisi) on the Quality of Orthodontic Finishing, Mini-Esthetics, and Anterior Tooth Tip and Torque: A Three-Arm Randomized Clinical Trial
试验速览
- 阶段
- 不适用
- 状态
- 已完成
- 入组人数
- 39
- 试验地点
- 1
- 主要终点
- Quality of orthodontic finishing - ABO Objective Grading System (ABO-OGS) total score
研究概览
简要总结
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.
详细描述
Bracket positioning is one of the most influential operator-dependent factors affecting the quality of orthodontic finishing and the resulting smile esthetics. Three contemporary positioning philosophies are compared in this trial.
Design. Eligible participants are randomly allocated 1:1:1 to one of three parallel arms. Allocation is generated with an online randomizer, concealed in sequentially opaque sealed envelopes held by a co-supervisor, and revealed only on the day of intervention. Outcome assessors are blinded; operator blinding is not feasible.
Intervention. All arms receive a fully digital indirect-bonding workflow (intraoral scanning, virtual bracket placement in 3Shape Ortho-Analyzer, 3D-printed casts, vacuum-formed transfer trays) using a 0.018-inch MBT prescription, and an identical arch wire sequence ending in a 0.017 in × 0.025 in stainless steel wire maintained for three months. The arms differ only in the vertical/angular bracket-positioning rule applied (SAP, SAMRA, or MBT chart).
Assessment. Records are captured before bonding (T₀) and at the end of levelling and alignment (T₁). The ABO-OGS is scored on 3D-printed casts and the panoramic radiograph; tip and torque are measured on dentoalveolar CBCT; mini-esthetic parameters are measured on standardized frontal posed-smile photographs calibrated in Adobe Photoshop.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Single (Outcomes Assessor)
入排标准
- 年龄范围
- 14 Years 至 25 Years（Child, Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Males and females aged 14-25 years with a full permanent dentition.
- •Mild to moderate crowding requiring non-extraction orthodontic treatment (2-6 mm per Graber's classification).
- •Angle Class I malocclusion.
- •Normal skeletal vertical dimension (SN-MP angle 32° ± 5°).
排除标准
- •1. Medication that may cause gingival inflammation (e.g., cyclosporine, phenytoin).
- •2. Impacted, extracted, or missing permanent teeth (except third molars).
- •Periodontal disease or parafunctional habits (bruxism, tongue thrusting, mouth breathing).
- •4. History of previous orthodontic treatment.
- •Craniofacial anomalies, facial asymmetry, or skeletal discrepancy.
结局指标
主要结局
Quality of orthodontic finishing - ABO Objective Grading System (ABO-OGS) total score
时间窗: At completion of the levelling and alignment phase (T₁), after the 0.017 in × 0.025 in stainless steel arch wire has been maintained for 3 months - approximately 7 months after bonding.
Total ABO-OGS score obtained on the Cast-Radiographic Evaluation (CRE) form. Seven parameters - alignment/rotations, marginal ridges, buccolingual inclination, occlusal contacts, occlusal relationships, overjet, and interproximal contacts - are scored on 3D-printed casts with the ABO measuring gauge; root angulation is scored on the panoramic radiograph. Point deductions are summed to give the total score (a lower total indicates better finishing).
次要结局
- Anterior crown angulation (tip) - CBCT(Change from before bonding (T₀) to end of levelling and alignment (T₁), approximately 7 months after bonding)
- Anterior crown inclination (torque) - CBCT(Change from before bonding (T₀) to end of levelling and alignment (T₁), approximately 7 months after bonding)
- Maxillary gingival display(Change from before bonding (T₀) to end of levelling and alignment (T₁), approximately 7 months after bonding)
- Maxillary incisal display(Change from before bonding (T₀) to end of levelling and alignment (T₁), approximately 7 months after bonding)
- Buccal corridor width(Change from before bonding (T₀) to end of levelling and alignment (T₁), approximately 7 months after bonding)
- Smile arc category(Change from before bonding (T₀) to end of levelling and alignment (T₁), approximately 7 months after bonding)
研究者
Hager Mansour Abdelbaseer Zoghby
Dr.
Future University in Egypt