A Point-of-Care Digital Workflow for 3D Printed Passive Presurgical Orthopedic Plates in Cleft Care.

Cleft lip and palate are one of the most common congenital craniofacial malformations. As an initial treatment, presurgical orthopedics is considered standard treatment at many cleft centers. Digital impressions are becoming feasible in cleft care. Computer-aided design (CAD) and three-dimensional (3D) printing are manufacturing standards in dentistry. The assimilation of these technologies has the potential to alter the traditional workflow for the fabrication of customized presurgical orthopedic plates. We present a digital workflow comprising three steps: 3D digital image acquisition with an intraoral scanner, open-source CAD modeling, and point-of-care 3D printing for the fabrication of personalized passive presurgical plates for newborns with cleft lip and palate. The digital workflow resulted in patient-related benefits, such as no risk of airway obstruction with quicker data acquisition (range 1-2.5 min). Throughput time was higher in the digital workflow 260-350 min compared to 135 min in the conventional workflow. The manual and personal intervention time was reduced from 135 min to 60 min. We show a clinically useful digital workflow for presurgical plates in cleft treatment. Once care providers overcome procurement costs, digital impressions, and point-of-care 3D printing will simplify these workflows and have the potential to become standard for cleft care.

Directional Notch trafficking in Sara endosomes during asymmetric cell division in the spinal cord.

Asymmetric division of neural precursor cells contributes to the generation of a variety of neuronal types. Asymmetric division is mediated by the asymmetric inheritance of fate determinants by the two daughter cells. In vertebrates, asymmetric fate determinants, such as Par3 and Mib, are only now starting to be identified. Here we show that, during mitosis of neural precursors in zebrafish, directional trafficking of Sara endosomes to one of the daughters can function as such a determinant. In asymmetric lineages, where one daughter cell becomes a neuron (n cell) whereas the other divides again to give rise to two neurons (p cell), we found that the daughter that inherits most of the Sara endosomes acquires the p fate. Sara endosomes carry an endocytosed pool of the Notch ligand DeltaD, which is thereby itself distributed asymmetrically. Sara and Notch are both essential for cell fate assignation within asymmetric lineages. Therefore, the Sara endosome system determines the fate decision between neuronal differentiation and mitosis in asymmetric lineages and thereby contributes to controlling the number of neural precursors and differentiated neurons during neurogenesis in a vertebrate.