Management of pharyngeal flap in cleft orthognathic surgery: speech outcomes and skeletal stability

The decision to either preserve or divide the pharyngeal flap during cleft orthognathic surgery (OGS) involves balancing maxillary advancement and maintaining velopharyngeal function. In this study, post-OGS velopharyngeal function and maxillary relapse were compared between patients with preserved and divided pharyngeal flaps. A retrospective review was conducted of cleft patients with a previous pharyngeal flap who underwent OGS between 2016 and 2020. Skeletal changes were evaluated via lateral cephalometry at three time-points: preoperative, immediately postoperative, and 1 year postoperative. Among the 26 patients included, 14 underwent pharyngeal flap preservation (PFP group) and 12 underwent pharyngeal flap division (PFD group). Horizontal A-point changes (A(X)) were significantly smaller in the PFP group (3.6 ± 2.0 mm) than in the PFD group (6.0 ± 2.3 mm) (P = 0.004). After OGS, velopharyngeal function deteriorated significantly more in the PFD group (75%) than in the PFP group (21.4%) (P = 0.016). Regression analysis suggested that pharyngeal flap division was associated with an increased risk of postoperative velopharyngeal function deterioration (odds ratio 14.06, P = 0.029), while horizontal maxillary surgical changes were inversely related to the maxillary relapse rate (regression coefficient = -0.79, P = 0.003). In conclusion, preserving the pharyngeal flap during cleft OGS is recommended to prevent speech deterioration without increasing the risk of maxillary relapse.