This systematic review examines the effectiveness of orthodontic treatment, particularly rapid maxillary expansion (RME), in managing obstructive sleep apnea syndrome (OSAS) in children. The study was conducted using databases such as Scopus, Web of Science, and PubMed, with keywords "OSA(S)" and "orthodontics." Sixteen publications were selected for analysis, focusing on clinical studies or case series related to OSA(S) children undergoing orthodontic treatment. RME was found to be the preferred orthodontic treatment for pediatric OSAS, aiming to increase the transverse diameter of the hard palate by reopening the mid-palatal suture. This procedure is particularly effective for children with maxillary contraction and dental malocclusion. However, OSAS is a multifactorial disorder, and orthodontic treatment alone may not be sufficient to address all aspects of the condition. The review also discusses the complications and management of OSAS, including adenotonsillectomy, continuous positive airway pressure (CPAP), medical therapy, bariatric surgery, and mandibular advancement devices. The long-term effectiveness of RME and its impact on upper airway volume and respiratory function were highlighted, along with the need for further research on mandibular advancement devices. The study concludes that early orthodontic intervention can be beneficial in managing pediatric OSAS, but additional studies are needed to establish the efficacy of various treatments.This systematic review examines the effectiveness of orthodontic treatment, particularly rapid maxillary expansion (RME), in managing obstructive sleep apnea syndrome (OSAS) in children. The study was conducted using databases such as Scopus, Web of Science, and PubMed, with keywords "OSA(S)" and "orthodontics." Sixteen publications were selected for analysis, focusing on clinical studies or case series related to OSA(S) children undergoing orthodontic treatment. RME was found to be the preferred orthodontic treatment for pediatric OSAS, aiming to increase the transverse diameter of the hard palate by reopening the mid-palatal suture. This procedure is particularly effective for children with maxillary contraction and dental malocclusion. However, OSAS is a multifactorial disorder, and orthodontic treatment alone may not be sufficient to address all aspects of the condition. The review also discusses the complications and management of OSAS, including adenotonsillectomy, continuous positive airway pressure (CPAP), medical therapy, bariatric surgery, and mandibular advancement devices. The long-term effectiveness of RME and its impact on upper airway volume and respiratory function were highlighted, along with the need for further research on mandibular advancement devices. The study concludes that early orthodontic intervention can be beneficial in managing pediatric OSAS, but additional studies are needed to establish the efficacy of various treatments.