Abstract
A girl, aged 7 years 1 month, had an anterior crossbite, crowding, and a skeletal Class I
jaw-base relationship. At phase 1 treatment, anterior crossbite and crowding were improved by using
a quad-helix for the maxillary arch and an expansion plate for the mandibular arch. At age of 13
years and 1 month, she had a diagnosis of anterior crowding with excessive posterior discrepancy and
labially-inclined maxillary incisors. Following extraction of bilateral maxillary and mandibular second
premolars, multibracket treatment was initiated. The treatment period with multibracket appliances
was 2 years and 10 months. The resultant occlusion was stable throughout a 5-year retention period.
Our results suggest the importance of evaluation of available space for not only anterior but also
posterior teeth alignment for long-term posttreatment stability.
