20 | wileyonlinelibrary.com/journal/ocr Orthod Craniofac Res. 2018;21:20–26. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd Accepted: 22 November 2017 DOI: 10.1111/ocr.12211 REVIEW ARTICLE Outcome of orthodontic palatal plate therapy for orofacial dysfunction in children with Down syndrome: A systematic review F. Javed 1 | Z. Akram 2 | A. P. Barillas 1 | S. V. Kellesarian 1 | H. B. Ahmed 3 | J. Khan 4 | K. Almas 5 1 Department of General Dentistry, Eastman Institute for Oral Health, University of Rochester, Rochester, NY, USA 2 Faculty of Dentistry, Department of Periodontology, Ziauddin University, Karachi, Pakistan 3 Private Dental Practitioner, Doha, Qatar 4 Department of Orofacial Pain and Temporomandibular Joint Disorders, Eastman Institute for Oral Health, University of Rochester, Rochester, NY, USA 5 Department of Preventive Dental Sciences, College of Dentistry, Imam Abdulrahman Bin Faisal University, Dammam, Kingdom of Saudi Arabia Correspondence Fawad Javed, Department of General Dentistry, Eastman Institute for Oral Health, University of Rochester, Rochester, NY, USA. Email: fawad_javed@urmc.rochester.edu Abstract To evaluate the effects of orthodontic palatal plate therapy (OPPT) in the treatment of orofacial dysfunction in children with Down syndrome (DS). Indexed databases were searched. Clinical trials in DS allocated to test (treatment with palatal plates) versus control group (without palatal plates/special physiotherapy for orofacial stimulation) with follow-up of any time duration and assessing mouth closure, tongue position, ac- tive and inactive muscle function as outcomes. Study designs, subject demographics, frequency and duration of palatal plate therapy, method for assessment, follow-up period and outcomes were reported according to the PRISMA guidelines. Eight clinical studies were included. The risk of bias was considered high in three studies and mod- erate in 5 studies. The number of children with DS ranged between 9 and 42. The mean age of children with DS at the start of the study ranged between 2 months and 12 years. The duration of palatal plate therapy ranged between 4 months and 48 months. The follow-up period in all studies ranged from 12 to 58 months. All stud- ies reported OPPT to be effective in improving orofacial disorders in children with DS. Most of the included studies suggest that palatal plate therapy in combination with physiotherapy/orofacial regulation therapy according to Castillo Morales/speech and language intervention seems to be effective in improving orofacial disorders in chil- dren with DS. However, the risk of bias of the included studies was high to moderate. Longitudinal trials with standardized evaluation methods, age of children at treatment initiation, treatment duration and standard orofacial outcomes are recommended. KEYWORDS Down syndrome, orofacial regulation therapy, palatal plate, systematic review 1 | INTRODUCTION Orthodontic treatment through orofacial regulation therapy (ORT) from the early childhood can monitor and rectify functional abnor- malities. 1 The objective of ORT is a dorsal cranial shift of the tongue, combined with automatic training of the muscles and stimulation of the inactive upper lip. 2 Orthodontic palatal plate therapy (OPPT) is an integral component of ORT that serves two main purposes, that is (i) improvement in oral motor function; and (ii) improving articulation. 3 However, palatal plate therapy alone may be inadequate and may re- quire adjunct treatment such as oral motor stimulation/physiotherapy. 4 Down syndrome (DS) is a chromosomal disorder caused by the pres- ence of a third copy of chromosome 21. This developmental disability occurs in almost 1:700-1000 births and poses a greater risk of medi- cal problems for the child. 5,6 Several cranial and orofacial dysmorphic features have been also described in children with DS, including small cranium, flattened face, slanted eyes, sloping under chin and low mus- cle tone in the orofacial region. 7,8 Lip closure is mostly poor, and the