[Measurement and analysis on the teeth morphology in 90 Chinese Han young adults with normal occlusion].

PURPOSE: To measure and analyze the teeth surfaces in 90 Chinese Han young adults with normal occlusion from one university in Shanghai, and to provide data for straight wire appliance system for Chinese patients. METHODS: 90 volunteers with normal occlusion were selected from 9000 college freshmen in Shanghai，whose dental impression with normal occlusion were scanned into digital models. Crown angulation, crown inclination, buccal(labial) crown facial prominence were measured and analyzed by Smartee Ortho（A）software. SPSS 17.0 software package was used for statistical analysis. RESULTS: The mean values of the teeth surfaces in normal occlusion were obtained, including crown angulation, crown inclination, buccal (labial) crown facial prominence. Crown angulations were leaning toward the middle line except upper second molars. Compared with west Caucasian, angulations were smaller in incisors and canines, and crown inclinations were larger in incisors and canines, especially the upper and lower canines. The upper and lower molars were inclined more to the lingual side. Crown facial prominence differences between upper first and second incisor were smaller, while the differences were larger between lower second incisor and canine, lower first and second molar. CONCLUSIONS: There are differences between Chinese and west Caucasian with normal occlusion. It is necessary to invent a kind of straight wire appliance system for Chinese patients.

Cotransplantation of glial restricted precursor cells and Schwann cells promotes functional recovery after spinal cord injury.

Oligodendrocyte (OL) replacement can be a promising strategy for spinal cord injury (SCI) repair. However, the poor posttransplantation survival and inhibitory properties to axonal regeneration are two major challenges that limit their use as donor cells for repair of CNS injuries. Therefore, strategies aimed at enhancing the survival of grafted oligodendrocytes as well as reducing their inhibitory properties, such as the use of more permissive oligodendrocyte progenitor cells (OPCs), also called glial restricted precursor cells (GRPs), should be highly prioritized. Schwann cell (SC) transplantation is a promising translational strategy to promote axonal regeneration after CNS injuries, partly due to their expression and secretion of multiple growth-promoting factors. Whether grafted SCs have any effect on the biological properties of grafted GRPs remains unclear. Here we report that either SCs or SC-conditioned medium (SCM) promoted the survival, proliferation, and migration of GRPs in vitro. When GRPs and SCs were cografted into the normal or injured spinal cord, robust survival, proliferation, and migration of grafted GRPs were observed. Importantly, grafted GRPs differentiated into mature oligodendrocytes and formed new myelin on axons caudal to the injury. Finally, cografts of GRPs and SCs promoted recovery of function following SCI. We conclude that cotransplantation of GRPs and SCs, the only two kinds of myelin-forming cells in the nervous system, act complementarily and synergistically to promote greater anatomical and functional recovery after SCI than when either cell type is used alone.