Correction of a true full-cusp unilateral posterior crossbite using mini-screw assisted biomechanics in an adult hyperdivergent patient.

Correction of a true unilateral posterior crossbite concurrent with space closure in the same dental arch side in an adult patient is demanding due to the potential iatrogenic biomechanical side effects on the contralateral unaffected side. The current case treatment strategy was aimed to manage the true unilateral posterior crossbite and space closure with minimal dentoalveolar undesirable effects by innovative application of a custom-made TAD (temporary anchorage device)-based palatal expander. In the present case report, non-orthognathic treatment of an adult female with unilateral upper right side true posterior crossbite is discussed. The patient revealed excessive gingival show at smile and upper midline deviation to the left side. The patient had also a previous history of first molar extraction on the crossbite side. The treatment was conducted by correcting the unilateral crossbite and space closure in the upper right side by using an innovative custom-made modification of hyrax anchored on TADs. Correction of the true full cusp unilateral crossbite, space closure, and midline deviation was accomplished. The patient's satisfactory aesthetic and occlusal results were obtained in 26 months with no undesirable complications in the opposite arch side. Innovative application of the miniscrew-based biomechanics could facilitate challenging treatments such as unilateral full cusp crossbite in adults with optimal final occlusal and aesthetic results and minimal undesirable complications.