Tehran University of Medical Sciences Journal of Craniomaxillofacial Research 2345-5489 8 1 2021 07 07 1 10 Mahsa Mortazavi Department of Orthodontics, University of the Pacific, Arthur A. Dugoni School of Dentistry, San Francisco, CA, USA. Reza Sharifi Craniomaxillofacial Research Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Oral and Maxillofacial Surgery, Tehran University of Medical Sciences, Tehran, Iran. Mahboube Hasheminasab Craniomaxillofacial Research Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Oral and Maxillofacial Surgery, Tehran University of Medical Sciences, Tehran, Iran. 2021 02 02 2021 02 20 Background: One of the most common maxillary abnormalities is transverse deficiency, which can be a contributory factor in malocclusions. There are some evidence of successful non-surgical treatment of this type of discrepancy after puberty by using maxillary expansion techniques. The Miniscrew-assisted rapid palatal expander (MARPE) method is a newly introduced method that has attracted the interest of many orthodontists. This study aimed to evaluate the therapeutic results of this technique in a systematic review. Materials and Methods: In this study, various databases including PubMed, Scopus, and ISI (Web of science) were queried with proper keywords, provided by PICO strategy of research, from 1980 to December 2020. Relevant articles were collected with restrictions on the English language. The full text of papers with all inclusion criteria was assessed. The therapeutic outcomes of MARPE were evaluated in the selected studies. Results: A total of 14 studies were included in the systematic review. Totally, 5 case report studies, 8 retrospective studies, and 1 case series study were reviewed. Cone-beam computed tomography was used as an outcome measure in all studies. In all reviewed studies, maxillary expansion occurred with high success rates in patients. Moreover, respiratory characteristics were also assessed in two studies measuring respiratory muscle strength, airflow and nasal and nasopharyngeal airway volume, showing benefits of MARPE. A study also examined three-dimensional soft tissue stereophotogrammetry. Based on these studies, the indication for using this method was a maxillary transverse deficiency as well as upper and lower arches crowding. No serious complications were reported in any of the reviewed studies. However, most studies did not perform long-term follow-ups and the age range of the subjects was mainly between 12 and 24 years. MARPE has been suggested as a treatment modality for correction of maxillary transverse deficiency in young adults but patients under the age of 14 may also benefit from this treatment in special conditions. Conclusion: A general review of the results of studies showed the high efficiency of MARPE technique in correcting maxillary transverse deficiency. Keywords: Maxillary transverse deficiency; Crossbite; Miniscrew; Miniscrew-assisted rapid palatal expander (MARPE). https://jcr.tums.ac.ir/index.php/jcr/article/view/360 https://jcr.tums.ac.ir/index.php/jcr/article/download/360/315