This case report presents the occlusion achieved after orthodontic treatment in a 17-year-old female patient with maxillary transverse deficiency, bilateral posterior crossbite, dental malocclusion, and Class II molar relationship. In the analysis of hayce nance performed at the beginning of the treatment, 8 mm of crowding in the maxilla and 1 mm of crowding in the mandible were recorded. In the posteroanterior cephalometric film, the maxillomandibular difference was measured as 3.4 mm maxillary transverse deficiency. On the lateral cephalometric film, skeletal class 1 relationship, optimal mandibular growth direction (SN/ GoGn=28), ?? upper incisors (1/SN=108) and lower incisors (1/MeGo=98) were found to be in normal values. For the treatment plan of the patient, fixed orthodontic treatment with rapid maxillary expansion, miniimplant assisted bilateral molar distalization was planned. The aim was to correct the posterior crossbite, achieve a Class I molar relationship, resolve maxillar constriction and achive a good occlusion. HYRAX expansion appliance was applied to the patient and expansion performed by activating the screw twice a day for a total of 24 days. On the 10th day, an occlusal radiograph showed opening in the median palatine suture, and on the 20th day, a diastema in the upper midline was observed on clinical examination. Distalization of maxillary molars was achived with a distalization mechanism using indirect anchorage from mini screws placed between canines and 1st premolars. Distalization of 4mm upper molars was obtained over a period of three months. After a total of twenty-five month of fixed orthodontic treatment, a Class I molar-canine relationship was achieved and an ideal occlusal relationship was established for both the upper and lower teeth.