Long term dental transversal stability of Class II division 1 treated with cervical headgear.

INTRODUCTION: In several conditions, outcome stability is a great challenge for Orthodontics. Previous studies have reported that relapse commonly occurs along the years after orthodontic treatment finishing. OBJECTIVE: The aim of the present study was to evaluate in the long-term transversal dental arch changes of Class II division 1 patients treated with cervical headgear and fixed appliance. METHODS: Plaster study casts of 20 patients treated with cervical headgear without dental extractions were 3D-scanned and evaluated in three distinct times: initial (T1), immediate post-treatment (T2) and long-term retention (T3 - minimum 20 years). Transversal teeth distance of maxillary and mandibular canines, premolars and first molars were measured. RESULTS: A statistically significant increase during treatment was observed for all maxillary teeth transversal distances (p< 0.05). In turn, a significant reduction was observed in the long term (p< 0.05). For the mandibular teeth, canine transversal distance presented statistically significant constriction in the retention period (p< 0.05). Mandibular first molars distance was significantly expanded by treatment (p< 0.05) and remained stable in the long term. The changes observed for the other teeth or other times were considered not statistically relevant. CONCLUSIONS: For the accessed sample, transversal changes occurred during treatment and retention phases in Class II division 1 patients treated with cervical headgear and fixed appliance. Relapse was considered statistically relevant, even with the institution of a retention protocol.

Long term dental transversal stability of Class II division 1 treated with cervical headgear

ABSTRACT Introduction: In several conditions, outcome stability is a great challenge for Orthodontics. Previous studies have reported that relapse commonly occurs along the years after orthodontic treatment finishing. Objective: The aim of the present study was to evaluate in the long-term transversal dental arch changes of Class II division 1 patients treated with cervical headgear and fixed appliance. Methods: Plaster study casts of 20 patients treated with cervical headgear without dental extractions were 3D-scanned and evaluated in three distinct times: initial (T1), immediate post-treatment (T2) and long-term retention (T3 - minimum 20 years). Transversal teeth distance of maxillary and mandibular canines, premolars and first molars were measured. Results: A statistically significant increase during treatment was observed for all maxillary teeth transversal distances (p< 0.05). In turn, a significant reduction was observed in the long term (p<0.05). For the mandibular teeth, canine transversal distance presented statistically significant constriction in the retention period (p<0.05). Mandibular first molars distance was significantly expanded by treatment (p<0.05) and remained stable in the long term. The changes observed for the other teeth or other times were considered not statistically relevant. Conclusions: For the accessed sample, transversal changes occurred during treatment and retention phases in Class II division 1 patients treated with cervical headgear and fixed appliance. Relapse was considered statistically relevant, even with the institution of a retention protocol.

RESUMO Introdução: Em várias condições, a estabilidade dos resultados é um grande desafio para a Ortodontia. Estudos prévios relataram que a recidiva ocorre, comumente, ao longo dos anos, após o término do tratamento ortodôntico. Objetivo: O objetivo da presente pesquisa foi avaliar as alterações transversais da arcada dentária em longo prazo de pacientes Classe II, divisão 1, tratados com aparelho extrabucal cervical e aparelho fixo. Métodos: Modelos de gesso de 20 pacientes tratados com AEB cervical, sem extrações dentárias, foram escaneados e avaliados em três momentos distintos: inicial (T1), pós-tratamento imediato (T2) e acompanhamento de longo prazo (T3, mínimo de 20 anos). A distância transversal entre os caninos superiores e inferiores, pré-molares e primeiros molares foi medida. Resultados: Foi observado aumento estatisticamente significativo durante o tratamento para todas as distâncias transversais dos dentes superiores (p < 0,05). Por sua vez, foi observada redução significativa em longo prazo (p < 0,05). Para os dentes inferiores, a distância transversal intercaninos apresentou constrição estatisticamente significativa no período de contenção (p < 0,05). A distância dos primeiros molares inferiores aumentou significativamente com o tratamento (p < 0,05) e permaneceu estável em longo prazo. As alterações observadas para os outros dentes ou outros tempos foram consideradas sem significância estatística. Conclusões: Para a amostra estudada, as alterações transversais ocorreram durante as fases de tratamento e contenção em pacientes Classe II, divisão 1, tratados com aparelho extrabucal de tração cervical e aparelho fixo. A recidiva foi considerada estatisticamente significativa, mesmo com a instituição de um protocolo de contenção.