Anterior tooth alignment and arch dimensions changes: 37-year follow-up in patients treated with and without premolar extraction
| Autor: | Augusto Iunes, Guilherme Janson, Karina Maria Salvatore de Freitas, Paula Cotrin, Caroline Martins Gambardela-Tkacz, Wilana Moura, Marcos Roberto de Freitas |
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| Rok vydání: | 2020 |
| Předmět: |
Adolescent
Cephalometry Orthodontics Malocclusion Angle Class II Perimeter 03 medical and health sciences 0302 clinical medicine Dental Arch stomatognathic system medicine Premolar Humans Bicuspid Arch business.industry Extraction (chemistry) Repeated measures design 030206 dentistry Craniometry medicine.disease Dental arch medicine.anatomical_structure Tooth Extraction EXTRAÇÃO DENTÁRIA Malocclusion business 030217 neurology & neurosurgery Follow-Up Studies |
| Zdroj: | Repositório Institucional da USP (Biblioteca Digital da Produção Intelectual) Universidade de São Paulo (USP) instacron:USP |
| Popis: | Introduction The objective of this research was to evaluate the anterior tooth alignment and dental arch dimension changes after orthodontic treatments with and without premolar extractions in the long-term. Methods Fifty-seven patients with Class I and Class II malocclusion were divided into 2 groups. Group 1 included 16 patients treated with nonextraction therapy, with mean initial (T1), final (T2), and long-term follow-up (T3) ages of 13.20 years, 15.07 years, and 50.32 years, respectively. The mean treatment (T2 − T1) and long-term follow-up (T3 − T2) times were 1.86 years and 35.25 years, respectively. Group 2 included 41 patients treated with extraction of 4 first premolars, with T1, T2, and T3 ages of 13.31 years, 15.63 years, and 53.60 years, respectively. The mean treatment and long-term follow-up times were 2.32 years and 37.96 years, respectively. The mean retention time was 2.26 years for both groups. The dental casts were obtained and digitized at T1, T2, and T3 stages. The following measurements were obtained: Little irregularity index, arch length, perimeter, and intercanine, interpremolar, and intermolar widths. Intragroup and intergroup comparisons were performed with repeated measures analysis of variance and t tests, respectively. Results Anterior tooth irregularity index increased at T3 in both groups. In addition, all arch dimensions, except the intercanine width, were significantly smaller in the extraction group at T3. Both groups showed similar arch dimension changes at T3, except for the mandibular arch perimeter. The percentage of mandibular anterior tooth alignment change was significantly greater in the nonextraction than in the extraction group. Conclusions There was no difference in the changes of anterior alignment and transverse arch dimensions in patients treated with and without premolar extraction at T3, but the percentage of mandibular anterior tooth alignment changes was higher in the nonextraction than in the extraction patients at T3. The mandibular arch perimeter showed more of a decrease at T3 in extraction patients. |
| Databáze: | OpenAIRE |
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