Rapid Maxillary Expansion For Class-II Malocclusion With Open Bite

Transverse maxillary deficiency is common in orthodontic patients. Rapid maxillary expansion(RME) increases arch width and length, relieving crowding and vertical interferences. This case report aims to present a non-extraction orthodontic approach using RME for Class II Division 2 malocclusion with severe maxillary crowding and open bite. A 16-year-old male with skeletal Class-I and Angle Class-II molar-canine relationship presented with the chief complaint of "poor occlusion". Maxillary constriction and severe maxillary crowding were present, along with posterior crossbite and anterior open bite. Minimal occlusal contact was observed at the central incisors and molars. 27 and 37 were mesially impacted. RME was used to widen the maxillary arch and correct the open bite. Implant anchorage and cantilever mechanics uprighted the impacted second molars. In 37 months, tongue-thrust habit was corrected, achieving well-aligned dentition, stable occlusion, and proper midline alignment. In the initial phase, RME corrected the transverse deficiency, widening and lengthening the arch to reduce crowding. As the teeth aligned, the vertical open bite caused by occlusal interference was corrected. A cantilever uprighted the maxillary left second molar, and implant anchorage helped upright the mandibular second molar, resolving impaction. The treatment achieved functional occlusion with Class I canine and molar relationships while preserving facial contours. Vertical malocclusion should be evaluated with horizontal interferences for effective three-dimensional correction. A phased treatment approach ensures stable results, optimizing occlusion and facial aesthetics.