The primary purpose of this study is to evaluate the dental and skeletal (orthopaedic) affects on the maxilla and its surrounding structures in response to rapid maxillary expansion treatment involving the use of active banded maxillary expansion appliance. This study involved two experimental groups, each consisted of 6 patients, aged 12 to 15 years wearing hyrax appliance (hygienic rapid maxillary basal arch expansion appliance). The rapid expansion period lasted 2-4 weeks , followed by a retention period of 12 weeks, followed by post-retention observations for 12 weeks. The results showed that (RME) appliances were capable of producing significant increases in intermolar width, palatal width, alveolar tipping, and molar tipping and were capable of expanding the maxilla.