RESUMEN
PURPOSE: To integrate digital dynamic smile aesthetic simulation (DSAS) cognitive education in orthodontic practicum and evaluate the teaching effects. METHODS: A total of 32 dental students during orthodontic practicum were randomly divided into two groups. One group received traditional teaching method to draft treatment plan, and another group was implemented with DSAS teaching method. Then two groups exchanged. Students were asked to grade both teaching methods and statistical analysis was performed on the scoring results with SPSS 24.0 software package. RESULTS: The scores of the DSAS teaching method was much higher than traditional method, and the difference was statistically significant(P=0.012). Students considered that DSAS teaching method was more "novel and fascinating", and also "convenient for comprehending of orthodontic treatment". Students hoped to popularize the DSAS teaching method in future orthodontic practicum. CONCLUSIONS: As a novel teaching method, DSAS is more intuitive and vivid to stimulate students' interest in learning, and it is helpful to improve the effect of orthodontic practical teaching.
Asunto(s)
Estética Dental , Aprendizaje , Humanos , Competencia Clínica , Atención Odontológica , Estudiantes , EnseñanzaRESUMEN
In the preliminary study, we have found an excellent osteogenic property of nanohydroxyapatite/chitosan/poly(lactide-co-glycolide) (nHA/CS/PLGA) scaffolds seeded with human umbilical cord mesenchymal stem cells (hUCMSCs) in vitro and subcutaneously in the nude mice. The aim of this study was to further evaluate the osteogenic capacity of nHA/CS/PLGA scaffolds seeded with hUCMSCs in the calvarial defects of the nude mice. Totally 108 nude mice were included and divided into 6 groups: PLGA scaffolds + hUCMSCs; nHA/PLGA scaffolds + hUCMSCs; CS/PLGA scaffolds + hUCMSCs; nHA/CS/PLGA scaffolds + hUCMSCs; nHA/CS/PLGA scaffolds without seeding; the control group (no scaffolds) (n = 18). The scaffolds were implanted into the calvarial defects of nude mice. The amount of new bones was evaluated by fluorescence labeling, H&E staining, and Van Gieson staining at 4 and 8 weeks, respectively. The results demonstrated that the amount of new bones was significantly increased in the group of nHA/CS/PLGA scaffolds seeded with hUCMSCs (p < 0.01). On the basis of previous studies in vitro and in subcutaneous implantation of the nude mice, the results revealed that the nHA and CS also enhanced the bone regeneration by nHA/CS/PLGA scaffolds seeded with hUCMSCs in the calvarial defects of the nude mice at early stage.
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Regeneración Ósea/fisiología , Trasplante de Células Madre de Sangre del Cordón Umbilical/instrumentación , Trasplante de Células Madre Mesenquimatosas/instrumentación , Fracturas Craneales/patología , Fracturas Craneales/cirugía , Andamios del Tejido , Animales , Quitosano/química , Trasplante de Células Madre de Sangre del Cordón Umbilical/métodos , Durapatita/química , Análisis de Falla de Equipo , Humanos , Ácido Láctico/química , Masculino , Ratones , Ratones Desnudos , Nanocompuestos/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico-Ácido Poliglicólico , Diseño de Prótesis , Fracturas Craneales/fisiopatología , Resultado del TratamientoRESUMEN
We aimed to evaluate the feasibility of the application of the nano-hydroxyapatite/chitosan/poly(lactide-co-glycolide) (nHA/CS/PLGA) scaffold seeded with human umbilical cord mesenchymal stem cells (hUCMSCs) in bone tissue engineering. We prepared the nHA/CS/PLGA, nHA/PLGA, CS/PLGA, and PLGA scaffolds, and tested their mechanical strength. We analyzed the surface antigen markers of hUCMSCs to determine their capability to differentiate into osteoblasts, chondrocytes, and adipocytes. The growth of hUCMSCs on the four types of scaffold was assayed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay (MTT assay) and observed using scanning electron microscopy (SEM). Quantitative analysis of alkaline phosphatase (ALP) activity and osteocalcin (OCN) content, as well as the semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) was performed. After 21 days, the subcutaneous implantations of the scaffolds samples seeded with hUCMSCs into nude mice were analyzed using immunohistochemical staining. The results showed that the mechanical strength of the nHA/CS/PLGA scaffold was enhanced. Furthermore, the nHA/CS/PLGA scaffolds were the most suitable for the adhesion, proliferation, and osteogenic differentiation of hUCMSCs in vitro and nude mouse subcutaneous implantation. The enhanced osteogenic inductivity of the nHA/CS/PLGA scaffolds for hUCMSCs might result from the addition of nHA and CS.