Modified bonded acrylic expander in patient with anterior crossbite and pseudo-class III

The open-bite treatment can be considered one of the most difficult malocclusions to treat in children as well as in adult patients. Several papers show that the traditional maxillary expander device contribute to increase the vertical face dimension and bite opening due to posterior rotation of the mandible, buccal tipping of lateral segments and cuspal interferences. Other more specific studies compared the effects of traditional maxillary expander to those of bonded acrylic expander and evidenced that the acrylic expander can better control the vertical effects of the maxillary expansion by the resin bite plane on which the heavy occlusal forces are exerted. We decided to use an acrylic expander in order to prevent worsening of anterior openbite after a careful assessment of nasal airflow by the otorhinolaryngologist.