I. Initial Examination and Diagnosis

Chief complaint: Irregular dentition with protrusive front teeth, affecting appearance and occlusion.
Findings:

• Protrusion of the upper anterior teeth with mild dental crowding;

• Lower arch crowding with Class II malocclusion;

• No obvious periodontal disease or history of dental caries.

Based on panoramic radiographs, cephalometric analysis, and intraoral examination, the diagnosis was Class II Division 1 malocclusion.

II. Treatment Plan

According to the patient’s condition, the following plan was designed:

1. Fixed appliance therapy (metal self-ligating brackets), with an estimated treatment duration of 20–24 months;

2. Extraction of the upper first premolars to provide sufficient space for alignment and retraction;

3. Placement of mini-screws for anchorage control to prevent relapse of anterior protrusion;

4. Post-treatment retention with retainers to maintain long-term stability.

III. Treatment Procedures

1. Extraction phase: Extraction of upper first premolars performed safely, followed by healing of the alveolar bone;

2. Bonding of brackets: Placement of self-ligating brackets on both arches, with progressive archwire changes;

3. Tooth movement and alignment: Application of light continuous force to align teeth and close extraction spaces;

4. Occlusal adjustment: Use of intermaxillary elastics to improve interarch relationship;

5. Finishing and retention: Final detailing of occlusion, removal of appliances, and delivery of retainers.

IV. Instructions and Precautions

1. Oral hygiene: Maintain meticulous brushing and interdental cleaning during treatment to prevent caries and gingivitis;

2. Dietary advice: Avoid hard and sticky foods to prevent damage to brackets;

3. Regular follow-ups: Visit every 4–6 weeks for adjustments according to tooth movement;

4. Retention phase: Wear retainers for at least 1–2 years after treatment to prevent relapse.

V. Expected Outcome

With standardized orthodontic treatment, significant improvement in anterior protrusion is expected. The dentition will become well-aligned, occlusion will be normalized, facial aesthetics will be enhanced, and both masticatory function and long-term oral health will benefit.