OBJECTIVES: This study aims to evaluate the differences in shear bond strength, marginal adaptation, and nano-microleakage after aging among snowplow, layered filling, and lining techniques applied to the resin-bonded restoration of defective primary teeth. METHODS: In this study, 51 freshly extracted, crown-intact primary anterior teeth and 30 primary molars were collected. The experimental groups were as follows: layered filling group, lining group, and snowplow group. Experiments were performed to compare the differences in shear bond strength, marginal integrity, and silver ion nano-microleakage after aging among these groups. RESULTS: The median shear bond strength of the layered filling group, lining group, and snowplow group were 2.45, 5.72, and 9.43 MPa, respectively. The values for lining group and snowplow group were significantly higher than that for layered filling group (P<0.05). No statistically significant difference was found between lining group and snowplow group (P>0.05). The median overall margin integrity of the layered filling group, lining group, and snowplow group were 55.38%, 48.25%, and 65.63%, respectively. The difference among the three groups was not statistically significant (P>0.05). The median percentages of silver ion nano-microleakage in the layered filling group, lining group, and snowplow group were 11.71%, 9.47%, and 11.55%, respectively. The difference among the three groups was not statistically significant (P>0.05). CONCLUSIONS Applying the snowplow technique to restore defective primary teeth can improve the bond strength and margin integrity and reduce nano-microleakage.
Tooth, Deciduous ; Humans ; Dental Restoration, Permanent/methods* ; Dental Leakage ; Shear Strength ; Dental Bonding/methods* ; Molar ; Composite Resins ; Silver

Objective:To observe the application value of "Internet +" based case teaching method combined with objective structured clinical examination (OSCE) teaching method in the teaching of nursing students in the Department of Nephrology, and analyze its impact on nursing student satisfaction of teaching.Methods:A total of 60 nursing students who practiced in the Department of Nephrology, Jiangsu Provincial People's Hospital from January 2021 to June 2022 were selected as the research subjects. They were randomly divided into observation group and control group, with 30 students in each group. The control group adopted traditional teaching method, and the observation group adopted case teaching method based on "Internet +" combined with OSCE teaching method. SPSS 25.0 statistical software was used for data analysis, and independent sample t-test was used to compare the clinical practical work ability and teaching satisfaction of the two groups of nursing students after teaching. Results:After 4 weeks of teaching, the total scores of clinical thinking ability, disease observation and evaluation ability, mastery of medical knowledge, standardized operation ability, communicative ability, adaptive ability, humanistic care and health literacy of the observation group were higher than those of the control group [(29.84±3.52) vs. (25.67±3.36), (5.81±1.52) vs. (4.34±1.67), (17.93±2.24) vs. (15.52±2.05), (25.72±2.73) vs. (22.17±2.56), (4.18±0.75) vs. (3.56±0.69), (83.48±6.67) vs. (71.26±7.05)], with a statistically significant difference ( P < 0.05); after 4 weeks of teaching, the teaching preparation, teaching process, teaching ability, teaching attitude, teaching effect and total score of the observation group were higher than those of the control group [(17.13±2.42) vs. (15.07±1.84), (36.44±3.12) vs. (34.07±2.49), (21.97±2.36) vs. (21.37±2.01),(17.00±2.36) vs. (16.83±2.23), (17.73±2.00) vs. (14.07±2.55), (110.27±5.51) vs. (101.40±4.58)], and the difference was statistically significant ( P<0.05). Conclusions:The case teaching method based on "Internet +" combined with OSCE can not only effectively improve the clinical practical work ability of nursing students in the department of nephrology, but also improve student satisfaction of teaching.

Objective To investigate the mechanism of mitochondrial division regulating myocardi-al fatty acid oxidation in diabetic mice.Methods A total of 16 7-week-old male SPF C57BLKS/J diabetic mice were randomly divided into model group and mitochondrial division inhibitor 1(mdivi-1)intervention group(intervention group),with 8 mice in each group.Another 8 male SPF C57BLKS/J mice of the same age were fed adaptively for 1 week and served as control group.The changes in blood glucose and body mass were monitored in above groups.Echocardiography was conducted to detect LVEF and LVFS1 rate and E/A between early and late ventricular diastole.The pathological changes of myocardial tissue were observed by HE staining.The size,morpholo-gy and quantity of mitochondria were observed by TEM.Western blotting was used to detect the expression of mitochondrial dynamin-related protein 1(Drp1),peroxisome proliferator activated receptor α(PPARα),long chain acyl-CoA synthetase 4(ACSL4),carnitine palmitoyl transferase 1B(CPT1B),and fatty acid oxidation detection kit was conducted to determine the activity of fat-ty acid oxidation.Results Compared with the control group,the model group presented hyper-trophic cardiomyocytes and significantly larger cross-sectional diameter of cardiomyocytes(22.36±2.80 μm vs 12.71±1.78 μm,P＜0.01)than the control group.Mdivi-1 intervention resul-ted in greatly improved myocardial hypertrophy and obviously smaller cross-sectional diameter of cardiomyocytes(13.79±1.39 μm vs 22.36±2.8 μm,P＜0.01)when compared with the model group.The expression level of myocardial mitochondrial Drp1,number of mitochondria per unit area of myocardial tissue and the protein levels of PPARα,ACSL4 and CPT1B in myocardial cyto-plasm were significantly higher,and the average mitochondrial area of myocardial tissue,the ex-pression of PPARα,ACSL4 and CPT1B in myocardial mitochondria,and fatty acid oxidation activ-ity were significantly lower in the model group than the control group(P＜0.01).After mdivi-1 intervention,the expression level of myocardial mitochondrial Drp1,the number of mitochondria per unit area of myocardial tissue and the protein levels of PPARα,ACSL4 and CPT1B in myocar-dial mitochondria were notably lower,and the expression of PPARα,ACSL4 and CPT1B in myo-cardial mitochondria and fatty acid oxidation activity in myocardial tissue were significantly higher when compared with those in the model group(P＜0.05,P＜0.01).Conclusion In diabetic mice,increased myocardial mitochondrial division,decreased translocation of fatty acid oxidation regula-tory protein from cytoplasm to mitochondria,inhibited fatty acid oxidation,and myocardial injury are observed.Mdivi-1 intervention inhibits mitochondrial division,promotes fatty acid oxidation by increasing the translocation of fatty acid oxidation regulatory proteins to mitochondria,and thus improves cardiac function.

Objective To investigate the mechanism of mitochondrial division regulating myocardi-al fatty acid oxidation in diabetic mice.Methods A total of 16 7-week-old male SPF C57BLKS/J diabetic mice were randomly divided into model group and mitochondrial division inhibitor 1(mdivi-1)intervention group(intervention group),with 8 mice in each group.Another 8 male SPF C57BLKS/J mice of the same age were fed adaptively for 1 week and served as control group.The changes in blood glucose and body mass were monitored in above groups.Echocardiography was conducted to detect LVEF and LVFS1 rate and E/A between early and late ventricular diastole.The pathological changes of myocardial tissue were observed by HE staining.The size,morpholo-gy and quantity of mitochondria were observed by TEM.Western blotting was used to detect the expression of mitochondrial dynamin-related protein 1(Drp1),peroxisome proliferator activated receptor α(PPARα),long chain acyl-CoA synthetase 4(ACSL4),carnitine palmitoyl transferase 1B(CPT1B),and fatty acid oxidation detection kit was conducted to determine the activity of fat-ty acid oxidation.Results Compared with the control group,the model group presented hyper-trophic cardiomyocytes and significantly larger cross-sectional diameter of cardiomyocytes(22.36±2.80 μm vs 12.71±1.78 μm,P＜0.01)than the control group.Mdivi-1 intervention resul-ted in greatly improved myocardial hypertrophy and obviously smaller cross-sectional diameter of cardiomyocytes(13.79±1.39 μm vs 22.36±2.8 μm,P＜0.01)when compared with the model group.The expression level of myocardial mitochondrial Drp1,number of mitochondria per unit area of myocardial tissue and the protein levels of PPARα,ACSL4 and CPT1B in myocardial cyto-plasm were significantly higher,and the average mitochondrial area of myocardial tissue,the ex-pression of PPARα,ACSL4 and CPT1B in myocardial mitochondria,and fatty acid oxidation activ-ity were significantly lower in the model group than the control group(P＜0.01).After mdivi-1 intervention,the expression level of myocardial mitochondrial Drp1,the number of mitochondria per unit area of myocardial tissue and the protein levels of PPARα,ACSL4 and CPT1B in myocar-dial mitochondria were notably lower,and the expression of PPARα,ACSL4 and CPT1B in myo-cardial mitochondria and fatty acid oxidation activity in myocardial tissue were significantly higher when compared with those in the model group(P＜0.05,P＜0.01).Conclusion In diabetic mice,increased myocardial mitochondrial division,decreased translocation of fatty acid oxidation regula-tory protein from cytoplasm to mitochondria,inhibited fatty acid oxidation,and myocardial injury are observed.Mdivi-1 intervention inhibits mitochondrial division,promotes fatty acid oxidation by increasing the translocation of fatty acid oxidation regulatory proteins to mitochondria,and thus improves cardiac function.