Therapeutic changes in extraction versus non-extraction orthodontic treatment

Area of Science:

• Orthodontics and Dental Research
• Craniofacial Development and Imaging

Background:

• Begg appliance therapy is a common orthodontic treatment modality.
• Understanding the cephalometric and clinical outcomes of different extraction strategies (first vs. second premolars) is crucial for treatment planning.

Purpose of the Study:

• To investigate the effects of extracting first premolars (E4), second premolars (E5), or non-extraction (NE) on crowding, incisor and molar positions, soft tissue profile, and clinical outcomes in patients treated with Begg appliances.
• To compare cephalometric and clinical results across the three treatment groups.

Main Methods:

• Lateral cephalograms and dental casts were analyzed pre- and post-treatment for 3 groups: E4 (n=?), E5 (n=?), and NE (n=?).
• Measurements included Arch Length Discrepancy (ALD) for initial crowding, incisor/molar positions, soft tissue profile changes, and the PAR Index for clinical outcome.
• Ten linear and eight angular cephalometric variables were assessed.

Main Results:

• Group E4 exhibited nearly double the pretreatment crowding compared to E5 and NE, correlating with higher initial PAR scores.
• Extraction groups showed a normalized inter-incisal angle, while the NE group's angle decreased. Upper incisors retracted ~2mm in extraction groups.
• All groups achieved >90% reduction in PAR Index, with post-treatment scores <2, indicating near-ideal clinical outcomes, and no unfavorable facial profile changes.

Conclusions:

• Extraction of first or second premolars, or non-extraction, when treated with Begg appliances, can yield excellent orthodontic results.
• Initial crowding severity is a key factor influencing treatment complexity and initial PAR scores.
• Begg appliance therapy effectively manages incisor and molar positions and soft tissue profiles across different extraction scenarios.