Abstract: This paper reports a case of severe torsion of maxillary incisor, whose root development was less than 1/2, with occlusal trauma in the early mixed dentition. The severely torsional incisor was firstly rotated and moved by removable appliance with double traction hooks to mildly torsional incisor, and then the mildly torsional incisor was aligned and leveled by replacing removable appliance with hyperbolic tongue spring and lip arch. Good results were achieved and the course of treatment was short.

Key words: the early mixed dentition, severe torsion of incisor, rotation movement, removable appliance