Effect of maxillary advancement on speech and velopharyngeal function of patients with cleft palate: Systematic Review and Meta-Analysis

This systematic review (SR) aimed to evaluate speech and velopharyngeal function (VPF) changes of patients with cleft palate (CLP) after maxillary advancement (MA) surgery. A two-phase PROSPERO-registered SR (CRD42019141370) was conducted following the PRISMA statements. Search strategies were developed for main databases (PubMed, Scopus, Web of Science, COCHRANE, LILACS, and EBSCOhost) and Grey literature information sources. The GRADE tool was used to evaluate the quality of evidence. From a total of 908 articles, 10 (205 men and 147 women; mean age ranging from 18.0 to 25.7 years) were selected for meta-analysis. Moderate to high risk of bias (Rob) was observed. The most common methods for outcomes evaluation were the Nasometer (speech) and nasoendoscopy (VPF). Speech changed from normal to hypernasal, and VPF worsening were reported in most studies. Comparing maxillary advancement interventions (osteogenic distraction versus Le Fort I), no statistically significant differences were found regarding benefit on speech and VPF. In summary, the effect of MA on speech and VPF remains controversial in CLP patients. The RoB, inconsistencies, and imprecisions severely affected the overall quality of evidence. Further adequately delineated clinical studies are necessary to investigate the potential effect of MA interventions on speech and VPF in CLP patients.