Phase I orthodontic treatment, often called early interceptive treatment, is a targeted, proactive approach for children typically between the ages of 6 and 10, during the mixed dentition stage (when they have a mix of baby and permanent teeth). Its primary goal is to address structural jaw growth or severe bite issues early on, creating a better foundation for the permanent teeth and reducing the need for more complex, invasive, or permanent tooth extraction treatments later. Treatment time is typically 6-15 months depending on the severity of treatment.