Patient with functional or esthetic complain (malocclusion) attending Dental Clinics in Al-Azhar University seeking orthodontic treatment, will be screened. Orthodontic young adult patients with transverse maxillary deficiency (as a primary diagnosis) will be selected from the list (by the study operator), based on inclusion and exclusion criteria. For this research purpose all subjects, whatever their number, who met the inclusion criteria, will be informed details of the expansion procedure, and about the whole study purposes, risks and benefits. Patient who agree to be a part of this research work, informed written consent will be taken from them. The patient will be divided randomly into two studying group, with a control group, Group A: (MARPE/ Conven), who will receive MARPE with its conventional expansion, and interventional group, Group B: who will receive a combination of MARPE/ALT-RAMEC technique. This randomization process will be carried out by the study operator using 30 sealed and shuffled envelopes, to blind both the operator and the participants during assignment to the groups. When a patient selects a group name, the operator will enroll him/her in the specific group list with allocation ratio 1:1 (15 patients in each group). Patient first visit (after assignment in the study) will take about 1 hour for preliminary evaluation, and T1 CBCT imaging. extra and intra oral assessment will be carried out to assess the dentition, occlusion type, periodontal status, and oral hygiene. Pretreatment CBCT imaging, gingival recession depths, and sulcus depths, will be taken as T1 records and interdental separating elastics will be used mesial and distal to 1st molars to provide adequate space for 1st molar banding.

Then a second visit will be required for impression taking, where orthodontic 1st molar bands will be selected and fitted properly in position for conventional alginate transfere impression to be taken for appliance laboratory construction. After that, dental separators will be reinserted again in their position. After which, and during the third visit (which might be the longest, 2 hours visit) the appliance will be loaded intraorally after local anesthesia infiltration using 4 mini-screws with previously planned length according to each patient palatal bone and soft tissue height. Then immediate activations (2-3 initial quarter turns), written hygiene, and activation instructions will be given to the patients in each group. In Group A (MARPE/conven) (Control), patients will open 2 quarter turn (0.2 mm) in the morning, and 2 quarter turn in the evening until overcorrection achieved. While in Group B (MARPE/ALT-RAMEC) (Interventional), patients will open 2 quarter turn (0.2mm) in the morning, and 2 in the evening in the first week, then alternate with closing 2 quarter turn in the morning and 2 in the evening in the second week. And then continuing opening and closing till end with opening in the 7th week and continue opening until overcorrection achieved. Patients will be followed up every week (1/2 an hour visit) for assessment of oral hygiene and interdental diastema appearance. In control group, if patients showed central diastema before 2-3 week , they will continue expansion till achieving overcorrection. But if they didn't show diastema after the 2-3 weeks, they will be terminated from the study and referred to maxillofacial surgery department for surgically assisted rapid palatal expansion (SARPE). In MARPE/ALT-RAMEC group, if patients showed diastema before 7-8 weeks of alternating expansion and constriction, they will continue only expansion till achieving overcorrection. But if they didn't; they will be terminated from the study and referred to maxillofacial surgery department for SARPE. All patients at the end of their expansion protocol, will get their T2 CBCT imaging and intra- oral measurements. Data collection from T1 and T2 CBCT records will be done by the study operator and then will be repeated again after 2 weeks of complete data collection by the same operator for data reliability. The patients who continue the expansion will be followed up until overcorrection is achieved which would take about 1-2 weeks after confirmation of median diastema event. The overall duration of participant involvement in group A (Control) is about 3-4 weeks, while in group B (Interventional) it will range from 8- 9 weeks.