RESUMO
There is still no unanimous agreement on the optimal surgical protocol(s) for the treatment of unilateral cleft lip and palate (UCLP), and a huge variety of protocols are employed by cleft centres across the world. The aim of this systematic review and meta-analysis was to compare reported patient outcomes of the Oslo protocol (and modifications) (OP) and delayed hard palate closure protocols (DHPCP) from a multidisciplinary perspective. A systematic search of multiple databases was conducted until September 2023. Studies reporting any patient outcomes of these protocols were included. Random-effects meta-analyses were performed for evidence synthesis, including comparisons of results between the types of protocol. The quality of evidence was evaluated using the ROBINS-I tool. In total, 62 articles (42 studies) reporting patients with UCLP were reviewed, involving 1281 patients following the OP and 655 following DHPCP. Equally poor long-term sagittal maxillofacial growth was found, and similar results for velopharyngeal insufficiency and nasolabial appearance. In contrast, OP was associated with a lower rate of oronasal fistulas. Disregarding the scarcity of comparable evidence for some domains, the results of this review, overall, favour OP over DHPCP. However, caution should be taken when interpreting the results on velopharyngeal insufficiency and oronasal fistulas, since the possibility of confounding and other biases remains.