Comparison of two methods for segmentation of the nasoalveolar defect and design of a three-dimensional surgical template in patients with cleft lip and palate: a retrospective study.

Alveolar bone grafting is an essential step in the treatment of cleft lip and palate. A method for designing a surgical template for the ideal graft volume and shape has been published previously. The aim of this study was to compare different software for the segmentation of the graft and design of the surgical template. Ten patients with unilateral cleft lip and palate were included. iPlan ENT was used for the first workflow and 3D Slicer and Blender for the second workflow. Every plan was done by two investigators. The planning time was compared between the two workflows and the two investigators. The results of the segmentation were compared by volumetric analysis. Planning with iPlan was significantly faster than 3D Slicer/Blender (P = 0.037 and P = 0.005, first and second planning by investigator 1; P = 0.017 for investigator 2). The median planning time for the experienced investigator was 297 s with iPlan and 390 s with 3D Slicer/Blender. The mean difference in graft volume was not significant (0.042 cm3). The mean ± standard deviation Hausdorff distance was 1.52 ± 0.57 mm and Dice similarity coefficient was 0.91 ± 0.02. These results show that both workflows are viable.