Treatment of Unilateral Crossbite with Orthodontic Expansion

Primary Treatment Approach

The American Academy of Orthodontics recommends maxillary expansion using a removable expansion plate or fixed expander as the evidence-based treatment of choice for functional unilateral posterior crossbite (FUPC), particularly when initiated in the late deciduous or early mixed dentition stage 1, 2

The American College of Radiology recommends panoramic radiography and lateral cephalogram as necessary for orthodontic diagnosis and treatment planning, while CBCT is not indicated for routine unilateral crossbite cases unless severe craniofacial dysmorphosis is present 3, 4

For children aged 5-8 years, the American Academy of Pediatric Dentistry recommends first-line treatment with a removable expansion plate with occlusal coverage, followed by retention for 6 months after correction, and monitoring for stability through adolescence 1
For children aged 8-12 years, the American Association of Orthodontists recommends fixed palatal expander (rapid maxillary expansion) as the treatment of choice, with activation of the expansion screw for 1-2 weeks, followed by consolidation of expansion without activation 1, 2