Seven-year-old patient in the first stage of mixed dentition, with a digital sucking habit. She presented the following alterations: anterior open bite, upper dentoalveolar protrusion, increased protrusion, bilateral posterior crossbite, maxillary compression and rotation of the occlusal plane. The growth pattern had a vertical tendency. In the myofunctional assessment, lip incompetence was observed.

Due to the unfavourable nature of the case, a combined treatment including orthodontic devices (quad-helix with lingual grid cemented in the upper first molars to produce maxillary expansion) was chosen, lingual arch cemented in the lower jaw to prevent the loss of the drift space and avoid extrusion of the lower molars and extraoral appliances (AEO) with high archwire to favour intrusion of the molars and thus allow the mandible to rotate forward and upward, closing the open bite), together with myotherapy exercises to increase lip tone. The duration of treatment was one and a half years.

