Craniofacial Computerized Tomography Analysis of the midface of patients with repaired complete unilateral cleft lip and palate

Introduction: Computerized tomography (CT) makes regional anatomy available as a series of cross-sectional axial images that can be analyzed unobstructed by other anatomic features. In this study, we aimed to analyze the maxillary dentoalveolar and deeper structures in patients with surgically repaired complete unilateral cleft lip and palate (CLP) and to investigate whether significant asymmetry existed in the deeper midfacial structures, using axial CT. Methods: Axial CT scans of 15 children (7 boys, 8 girls; mean age, 11.59 ± 1.34 years) with repaired complete unilateral CLP were acquired parallel to Reid's base line. Specific landmarks applicable for CT were defined and plotted to undertake a comprehensive Craniofacial CT Analysis of the midface. Twenty-six pairs of transverse and sagittal measurements made to a cranial base midsagittal construct and interspinosum fit line, respectively, were compared by using the paired t test. Results: Significant reduction of 19.05% in the nasal chamber width (2.54 ± 1.49 mm; P <0.001), more distal position of the bony alar base (2.28 ± 1.71 mm; P <0.001), and the sagittal position of the most prominent anterolateral point on the maxillary alveolar process (1.62 ± 1.85 mm; P <0.01) were noted on the cleft side. The lower half of the bony nasal septum was consistently deviated toward the cleft side, and the nasal tip was deviated to the noncleft side in 60% of the subjects. The anterior nasal spine was deviated to the noncleft side in 73.3% of the subjects and a mean deviation of the anterior nasal spine of 2.84 ± 3.90 mm toward the noncleft side was measured. Significant sagittal and transverse asymmetry in deeper midfacial regions was not observed. Unilateral dental-arch collapse was observed in 73.3% of the sample, bilateral collapse in 20%, and no collapse in 6.7%. The soft-tissue support of the alveolar margins of the cleft did not show significant differences between the cleft and noncleft sides. Conclusions: CT is an excellent method for quantifying surface and deep craniofacial structures. Most asymmetries and deformities in the 10- to 14-year-old patients with repaired complete unilateral CLP we studied were in the dentoalveolar area near the cleft and the nasal chamber and not in the deeper regions of the maxillary complex.