Comparing Leaf Expander and Hyrax Expander in Children 6-12 Years Old With Posterior Crossbite During Mixed Dentition

What this Trial Is About

This research evaluates two types of maxillary expansion devices in children aged 6 to 12 years with posterior crossbite and mixed dentition. The trial compares a leaf expander using nickel-titanium springs with a traditional Hyrax expander that requires manual activation. The study aims to assess differences in pain experienced during the first week after device insertion and observe skeletal and dental changes over time. Conducted as a randomized clinical trial, the study is sponsored by Cairo University. Participants receive an appliance cemented to their upper first permanent molars. One group uses a 9 mm leaf expander delivering approximately 900 g of force without requiring home adjustments. The other group uses a 9 mm Hyrax expander with a screw that participants activate twice weekly. After achieving the planned expansion, both devices remain passively in place for a 6-month retention period to maintain the correction. Throughout the study, children report daily pain levels for the first 7 days following insertion. Researchers also use imaging and digital models to measure skeletal expansion, dental tipping, and other parameters six months after expansion completion. The total follow-up period includes initial treatment and retention, with ongoing assessments to monitor outcomes and device effects.

Leaf Expander Versus Hyrax Expander in Mixed Dentition Patients With Posterior Crossbite.