Correction of upper midline diastema and crowding in a Class I malocclusion with skeletal Class II pattern

A 17-year-old female presented with concerns about spacing on her upper teeth, crowding, and facial asymmetry. Clinical and radiographic evaluations revealed Angle Class I malocclusion with a skeletal Class II base, anterior crowding in the lower arch, central diastema associated with a high labial frenulum, proclined incisors, and a deep bite. The patient also had a unilateral chewing habit for the past two years. Treatment: A non-extraction orthodontic plan was carried out using pre-adjusted MBT fixed appliances. Treatment began with scaling, oral hygiene education, and frenectomy. Archwire sequencing, torque correction, elastic use, and bite-opening mechanics were employed to align teeth, close diastema, and achieve occlusal and facial balance. Retention was maintained using fixed lingual retainers. Results: Post-treatment assessment showed improved facial profile, reduced facial convexity, normalized maxillomandibular skeletal relationship (Class I), decreased incisor proclination, and an increased nasolabial angle. However, the lips remained slightly anterior to the aesthetic line. Conclusion: This case demonstrates that a well-planned, non-extraction orthodontic approach, combined with surgical adjuncts and individualized biomechanics, can effectively manage Class I malocclusion with skeletal Class II features and achieve both functional and esthetic outcomes.