Class II division 1 treatment with extractions

Marcello M. | March 13, 2025

Long-term stability of Class II division 1 treatment with extractions

Proffit WR, Fields HW, Sarver DM.

American Journal of Orthodontics and Dentofacial Orthopedics (2007).

For any orthodontist, one of the most critical questions in treatment planning is whether to extract teeth in Class II Division 1 cases. While extractions can be beneficial in achieving a well-aligned and functional occlusion, their long-term impact on stability remains a subject of debate. The landmark study by Proffit, Fields, and Sarver (2007), published in the American Journal of Orthodontics and Dentofacial Orthopedics, provides invaluable insights into this issue. This article aims to break down the key findings of the study, emphasizing their practical implications for young orthodontists.

Study Overview

Research Objective

The study investigated the long-term stability of orthodontic treatments involving extractions in Class II Division 1 patients. It specifically examined whether extraction-based treatments maintain their results years after completion.

Methodology

• Study Population: Patients with Class II Division 1 malocclusion who underwent orthodontic treatment with extractions.
• Data Collection: Longitudinal analysis of occlusal outcomes, dental positioning, and skeletal relationships before treatment, immediately after treatment, and years post-treatment.
• Measurement Tools: Cephalometric radiographs, dental casts, and clinical assessments.

Key Findings

1. Extractions Improve Occlusion but Stability Is Not Guaranteed

The study confirmed that extractions significantly enhance occlusion and overall alignment. However, it also revealed a tendency toward post-treatment relapse, particularly in the anterior segment.

2. Risk of Relapse and Unstable Anterior Alignment

Many patients experienced minor dental shifts years after treatment, particularly in the lower incisors. These changes highlight the importance of long-term retention strategies.

3. Retention Strategies Are Crucial

The study reinforced that retention plays a decisive role in preventing relapse. Without appropriate retention measures, even a well-executed treatment plan can lose its effectiveness over time.

Clinical Implications for Young Orthodontists

1. Extraction-Based Treatments Require Careful Case Selection

Before deciding on extractions, young orthodontists should consider:

• The severity of crowding and arch length discrepancy
• Facial profile changes post-extraction
• Potential long-term occlusal stability

2. Retention Protocols Should Be Personalized

A one-size-fits-all approach does not work for retention. Instead:

• Patients with higher relapse risks (e.g., significant incisor movement) should use long-term fixed retainers.
• Compliance with removable retainers should be reinforced through patient education.

3. Patient Education Is Key

• Patients must understand that orthodontic treatment is a lifelong commitment, and retention is essential.
• Explaining the risks of relapse can improve adherence to retention protocols.

Final Thoughts: What This Means for Your Future Practice

As an orthodontist, understanding the long-term effects of extractions will shape your decision-making process. This study by Proffit et al. serves as a foundation for evidence-based practice, emphasizing that achieving an ideal occlusion is only the beginning—maintaining it requires strategic retention planning and patient cooperation.

Takeaway: Extractions can be a valuable tool in treating Class II Division 1 malocclusions, but their long-term success depends on thorough case selection, robust retention strategies, and ongoing patient education.

For any orthodontist aiming to provide stable and aesthetic results, this study is a must-read. Keep it in mind as you refine your clinical judgment and treatment planning skills!