Non-surgical treatment of severe anterior open bite, hyperdivergent pattern, and posterior crossbite in an adult with atrophy of the mandibular first molar extraction site: A case report.

Anterior open bite presents a significant challenge in orthodontic treatment due to its multifactorial aetiology. Managing such cases in adult patients is further complicated when additional factors, such as posterior crossbite, are present. Space closure in an atrophic edentulous ridge poses an added challenge due to reduced alveolar bone width and the risk of periodontal compromise. The diagnostic and treatment details of the present case were documented in accordance with the CARE guidelines for clinical case reporting. This case report describes the successful non-surgical management of an 18-year-old female with severe anterior open bite, hyperdivergent facial morphology, bilateral posterior crossbite, and an atrophic mandibular first molar extraction site with a mesially and lingually tipped second molar. The patient declined orthognathic surgery, leading to the consideration of a comprehensive orthodontic approach in conjunction with Miniscrew-Assisted Rapid Palatal Expansion (MARPE) for transverse correction, skeletal anchorage for maxillary molar intrusion, and fixed orthodontic appliances for space closure and molar uprighting. Treatment resulted in a functional occlusion with Class I molar and canine relationships, normal overjet and overbite, and stable transverse correction. The patient received satisfactory facial aesthetics with a harmonious smile and was pleased with the results. The integration of skeletal anchorage enabled effective vertical and transverse correction in an adult patient without orthognathic surgery. Controlled uprighting with intrusion allowed for proper alignment of a tipped mandibular molar, followed by successful protraction across an atrophic ridge.