Evaluation of Lefort I Osteotomy Line and Pterygomaxillary Junction Region in Patients With Cleft Lip and Palate

Objective: This study aimed to evaluate the Le Fort I osteotomy line and pterygomaxillary junction via cone-beam computed tomography in individuals with cleft lip and palate (CLP). Design: Retrospective study. Patients and Methods: The study included individuals older than 16 years with CLP, who were scheduled for repositioning of the maxilla by Le Fort I osteotomy, and those with class III malocclusion with maxillary hypoplasia, who were scheduled for Le Fort I osteotomy. The measurements made in the area of the cleft of individuals with CLP were compared with both the side with no cleft and those with class III malocclusion with maxillary hypoplasia. A total of 11 measurements were made on the axial section parallel to the Frankfurt Horizontal plane, corresponding to the lower 1/5 of the distance between the infraorbital foramen and the anterior nasal spine. Results: There were significant differences both in the comparisons made between the individuals with CLP and those without CLP in terms of the canal-anterior alveolar crest (G) and sinus-anterior alveolar crest (L) measurements ( P < .05). The mean measurement values showed that the measurement results were higher in individuals with CLP in general. Conclusion: In conclusion, we believe that there might be difficulties both in osteotomy and down fracture stages during Le Fort I osteotomies performed in individuals with CLP.

Morphologic Evaluation for Safe Le Fort I Osteotomy in Cleft Lip and Palate

Objective: The present study aimed to determine the structure and morphology of the maxilla in patients with cleft lip and palate to ensure safe Le Fort I osteotomy. Patients: A total of 34 sides of 17 patients with unilateral cleft lip and palate (nonsyndromic cases) were included in this study. The control group included 10 sides of 5 patients who exhibited skeletal mandibular protrusion without malformation. Methods: Finite element analysis was performed to examine the distribution of occlusal force over the maxilla, and continuous 3-dimensional measurement was performed at the sites of stress concentration. Results: In patients with cleft lip and palate, bones at the lateral border of the piriform aperture and the anterior wall of the maxillary sinus were significantly thicker than those in controls ( P < .05). Furthermore, the attachment of the pterygomaxillary junction was wider and thicker ( P < .05), and the anterior distance to the descending palatine artery was shorter ( P < .01) in patients with cleft lip and palate than in controls. Our results further indicated that alveolar bone grafting may significantly influence bone thickness and the attachment state of the pterygomaxillary junction. Conclusions: Our results suggest that the complications of LFI can be reduced in patients with cleft lip and palate by ensuring proper understanding of each patient’s maxillary anatomy and bone thickness, as well as the location of the descending palatine artery and the attachment state of the pterygomaxillary junction.