One-Year Stability of LeFort I Advancement in Patients With Complete Cleft Lip and Palate Using a Standardized Clinical and Surgical Protocol

Aim: To assess treatment outcome and 1-year stability of LeFort I advancement in patients with complete cleft lip and palate. Methods: Thirty-five patients (age 20.65 +/- 2.20 years) with unilateral (n = 25) or bilateral (n = 10) complete cleft lip and palate who underwent LeFort I advancement were included. Lateral cephalograms before surgery (T1), immediately postsurgery (T2), and at 1-year follow-up (T3) were superimposed, and the position of anterior nasal spine (ANS), A-point, and U1 Tip assessed using an x, y coordinate system. Differences between landmark positions at the 3-time points were analyzed using paired sample t-tests, with a significance defined as alpha <= 0.05. Results: The mean surgical advancement in the horizontal direction (T2-T1) was 6.50 +/- 2.62 mm at ANS (P < 0.001) and 7.05 +/- 2.51 mm at A-point (P < 0.001). At a 1-year follow-up (T3-T2), the mean horizontal relapse at ANS was -1.41 +/- 1.89 mm (P < 0.001) and -0.79 +/- 1.48 mm at A-point (P 0.003). Mean horizontal relapse was 21.7% and 11% of surgical advancement when assessed at ANS and A-point, respectively. The central incisor tip position remained stable during the postsurgical period (0.12 +/- 2.11 mm, P 0.732). At A-point, the mean vertical surgical change (T2-T1) was -0.96 +/- 2.57 mm (P < 0.001). No significant post-treatment (T3-T2) vertical changes were detected at ANS or A-point. Phenotypic stability was excellent, with all patients maintaining positive overjet at 1-year follow-up. Conclusions: LeFort I advancement in complete cleft lip and palate is stable, with less than a 2 mm relapse after 1-year. Surgical overcorrection by 10% to 20% is recommended to compensate for the expected skeletal relapse.