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Arch width changes in patients with Class II division 1 malocclusion treated with maxillary first premolar extraction
Sajjad Shirazi1, Mojgan Kachoei2, Naiemeh Shahvaghar-Asl3
1Lecturer and Faculty Member, Faculty of Dentistry, Tabriz University of Medical Sciences, Tabriz, Iran; Research Fellow, Dental and Periodontal Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Journal of Clinical and Experimental Dentistry
|October 6, 2016
Summary
Arch width generally increases during orthodontic treatment for Class II division 1 malocclusion, whether or not maxillary first premolars are extracted. However, the maxillary inter-molar width decreased in extraction cases.
Area of Science:
- Orthodontics
- Dentofacial Orthopedics
Background:
- Class II division 1 malocclusion presents unique challenges in orthodontic treatment planning.
- Understanding arch width changes is crucial for successful treatment outcomes.
Purpose of the Study:
- To evaluate arch width alterations in patients with Class II division 1 malocclusion.
- Compare changes between extraction and non-extraction treatment protocols.
Main Methods:
- Analysis of dental casts from 91 adult patients (age >16) with Class II division 1 malocclusion.
- Measurement of pre- and post-treatment maxillary and mandibular inter-canine and inter-molar widths.
- Comparison between 48 extraction and 43 non-extraction cases.
Main Results:
- Significant increases in maxillary and mandibular inter-canine widths observed in both groups.
- Maxillary inter-molar width decreased with extraction but increased without extraction.
- Mandibular inter-molar width increased significantly in both treatment groups.
Conclusions:
- Orthodontic treatment, both with and without premolar extraction, tends to increase arch width.
- Maxillary inter-molar width is an exception, showing a decrease in extraction cases.
- Treatment outcomes for arch width changes were consistent between genders.
