Objective:To explore the morphology and vessel distribution of the scapholunate interosseous ligament and anatomical basis for the clinical reconstruction of scapholunate interosseous ligament.Methods:From October, 2018 to December, 2018, 12 fresh wrist joint specimens were perfused with gelatin-lead oxide solution from ulnar or radial artery and scanned under micro-CT. The morphology of scapholunate interosseous ligament in neutral position and the distribution of nutrient vessels in the ligament were observed on reconstructed 3D images by Mimics. The width, length and thickness of palmar, dorsal and proximal ligaments were measured. The anatomical parameters at the entrance of nutrient vessels in the scapholunate interosseous ligament were taken and their relationship with the blood supply to the scapholunate was analyzed.Results:①For scapholunate interosseous ligament, it was found that the average length of the proximal sub-region was the longest, the length of palmar and dorsal sides was similar to each other and the widest and thinnest was in palmar side, while the thickness and width of dorsal and proximal were similar. ②There was no nutrient vessel in the proximal part of the scapholunate interosseous ligament. But there were abundant nutrient vessels in the palmar and dorsal scapholunate interosseous ligament, and there was no significant difference in blood supply to palmar and dorsal scapholunate interosseous ligament ( P>0.05). ③The palmar and dorsal medial nutrient vessels that supply to the scapholunate interosseous ligament enter the scapholunate from the attachment of ligament of scapholunate interosseous joint. Conclusion:The palmar side of the scapholunate interosseous ligament is wider and thinner than that of the other subareas, which makes it more vulnerable to injury from an anatomical point of view. There is abundant blood supply to the palmar and dorsal subareas of the scapholunate interosseous ligament and the supplying vessels anastomose inside the scapholunate bone. There is no distribution of blood vessel at the proximal part of scapholunate interosseous ligament, hence is difficult to heal. An injury of palmar and dorsal ligaments may affect the blood supply of scapholunate.

Peripheral nerve injury (PNI) is a common disease in the oral cavity that can easily lead to loss of function and abnormal appearance. The application of dental pulp stem cells (DPSCs) combined with tissue engineering in the repair of PNI is a research hotspot. DPSCs have the advantages of abundant sources, simple extraction, low immunogenicity and a high proliferation rate in vitro. They can differentiate into Schwann cells (SCs). SCs can induce autophagy and secrete key neurotrophic factors, such as nerve growth factor, brain-derived neurotrophic factor, ciliary neurotrophic factor and glial cell-derived neurotrophic factor. SCs are beneficial for the repair of nerve injury. DPSCs in different periods have differences in immune regulation, anti-inflammatory effects, expression of neural markers, angiogenesis and so on, which provide more diversified choices for nerve repair. At present, the introduction of tissue engineering provides a more controllable and improved microenvironment for DPSCs, which is conducive to the application and development of DPSCs in regenerative medicine and tissue engineering. However, there are still many problems to be solved, such as the selection of stem cells, functional link recovery, uncontrollable direction of axon regeneration, regulation of the peripheral nervous system and mechanism of repair.

Objective:To investigate the response of mandibular condylar chondroprogenitors to flow fluid shear stress(FFSS).Methods:Chondroprogenitors were in vitro cultured and stimulated with FFSS that can cause cell degeneration,and treated with sec-ond-generation high-throughput RNA sequencing.Differential gene expression was screened using DESeq2 software for gene ontology(GO)functional enrichment analysis,kyoto encyclopedia of genes and genomes(KEGG)pathway enrichment analysis and protein-protein interaction(PPI)network analysis.qRT-PCR was performed to validate the core genes screened by PPI.Results:A total of 1996 differentially expressed genes were obtained,mainly including inflammatory response and cell cycle related molecules.Among them,Actal,Atf3,Ccl2,116,Nfkbia,Ret and Vcaml were identified as the core genes.Conclusion:FFSS stimulation affects chondroprogenitor function by acting on inflammatory responses and cell cycle-related signaling pathways in chondroprogenitors.