Maxillary anterior alignment stability in Class I and Class II malocclusions treated with or without extraction
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Published on: February 23, 2024
Willian Juarez Granucci Guirro1, Karina Maria Salvatore Freitas2, Guilherme Janson3
1a Orthodontic graduate student, Department of Orthodontics, Bauru Dental School, University of São Paulo, São Paulo, Brazil.
Objective:
To compare the postretention stability of maxillary incisors alignment in subjects with Class I and II malocclusion treated with or without extractions.
Materials And Methods:
The sample comprised 103 subjects with initial maxillary anterior irregularity greater than 3 mm and was divided into four groups: group 1 comprised 19 patients with Class I malocclusion treated with nonextraction (mean initial age = 13.06 years); group 2 comprised 19 patients with Class II malocclusion treated with nonextraction (mean initial age = 12.54 years); group 3 comprised 30 patients with Class I malocclusion treated with extractions (mean initial age = 13.16 years); group 4 comprised 35 patients with Class II malocclusion treated with extractions (mean initial age = 12.99 years). Dental casts were obtained at three different stages: pretreatment (T1), posttreatment (T2), and long-term posttreatment (T3). Maxillary incisor irregularity and arch dimensions were evaluated. Intergroup comparisons were performed by one-way analysis of variance followed by Tukey tests.
Results:
In the long-term posttreatment period, relapse of maxillary crowding and arch dimensions was similar in all groups.
Conclusion:
Changes in maxillary anterior alignment in Class I and Class II malocclusions treated with nonextractions and with extractions were similar in the long-term posttreatment period.
