Vertical versus horizontal morphology of congenital alveolar cleft defects: A one-year comparative study on clinical, radiographic, and biochemical outcomes.

Abstract

<h4>Objectives</h4>Reconstruction of congenital alveolar clefts presents a uniquely complex surgical challenge. This study aimed to comprehensively evaluate the one-year clinical, radiographic, and biochemical outcomes of guided bone regeneration in patients with distinct horizontal versus vertical morphologies of congenital alveolar clefts during oral implant placement.<h4>Materials and methods</h4>This retrospective cohort study included 240 patients with congenital unilateral alveolar clefts treated between January 2018 and December 2023. Patients were allocated into a horizontal defect group (n = 120) or a vertical defect group (n = 120) based on cone-beam computed tomography (CBCT) classification. All patients received autogenous particulate bone grafts from the iliac crest stabilized with titanium mesh. Outcomes assessed over a 12-month period included clinical success rate, radiographic bone changes, trabecular microarchitecture, serum biomarker levels (BMP-7, TGF-β1, bFGF, and VEGF), complications, and patient-reported outcomes.<h4>Results</h4>At the 12-month follow-up, the vertical defect group demonstrated a significantly higher "excellent" reconstruction rate (95.8 % vs. 79.1 %, P < 0.001) and superior implant survival (98.3 % vs. 91.7 %, P = 0.021). CBCT analysis revealed that the vertical group maintained significantly greater alveolar bone height and width at 12 months (P < 0.001). The vertical group also exhibited superior trabecular maturation (P < 0.001). Serum concentrations of bone morphogenetic protein-7 (BMP-7), transforming growth factor-β1 (TGF-β1), and vascular endothelial growth factor (VEGF) were significantly higher in the vertical group at 4 and 8 weeks post-surgery. Furthermore, the vertical group reported significantly lower rates of complications and better Oral Health Impact Profile-14 (OHIP-14) scores (P < 0.01).<h4>Conclusion</h4>Morphology-guided bone augmentation for congenital alveolar clefts shows that vertical ("box-like") defects yield superior one-year outcomes over horizontal ("saucer-shaped") defects. The favorable biomechanical containment of vertical defects appears to promote enhanced graft consolidation, likely through improved neovascularization and a more robust osteogenic signaling cascade, leading to improved implant stability and patient satisfaction.