Cephalometric Evaluation of Airways After Maxillary Anterior Advancement by Distraction Osteogenesis in Cleft Lip and Palate Patients: A Systematic Review

Objective: This study was conducted to review the changes in airways after maxillary anterior advancement by distraction osteogenesis in patients with cleft lip and palate. Materials and Methods: Several electronic databases were searched. The selection criteria were set to include clinical trials and at least 1 year of postsurgical data. The original articles were then retrieved and evaluated by two investigators to ensure that they met the selection criteria. The references were also hand searched for possible missing articles. Results: Forty-three abstracts were found in the electronic searches. After the first set of selection criteria was applied to these abstracts, 14 articles were retrieved. After the final selection criteria, only four articles were finally selected. However, sample sizes of the selected articles were small, and the methodological quality of the studies was inadequate. All selected articles were consistent in that upper airway sizes increased and nasal resistance was reduced after distraction osteogenesis. Conclusions: Despite the consistency of increasing the upper airway size and reducing nasal resistance in the only four found articles, limitations of the studies merit caution in interpreting these findings. We conclude that there are insufficient prospective randomized controlled clinical trials to confirm these results.