Effects of Four First Premolar Extraction on the Upper Airway Dimension in a NonGrowing Class I Skeletal Patients: A Systematic Review

Abstract

Objective: Orthodontic treatment aims not only to treat one's malocclusion and facial aesthetics but also to maintain or improve the patient's airway patency. This review aims to evaluate post-treatment changes in the position of hyoid bone and oropharyngeal airway size and dimensions associated with fixed orthodontic treatment with four first bicuspid extractions in non-growing Class I skeletal bimaxillary protrusion individuals. Methods: Electronic databases including Embase, Web of Science, PubMed, and Scopus were used to research published articles. Included studies assessed the post-treatment effects of four first bicuspid extractions with maximum anchorage on pharyngeal airway dimensions in non-growing patients. Relevant data were obtained, summarised, and analysed from the included studies. 75% retraction; tooth