BACKGROUND:NovaMin is a kind of bioactive glass, and its active ingredients react with saliva to form hydroxyapatite crystals, which deposit on the surface of the teeth and can close the exposed dentinal tubules. It can be used for the treatment of dentin hypersensitivity.
OBJECTIVE:To study the effect of toothpaste containing NovaMin on tooth hypersensitivity patients after subgingival scaling and root planing surgery.
METHODS:According to inclusion and exclusion criteria, 96 patients were picked out from 543 patients to participate in the experiment. In compliance with the principle of randomized, double-blind, comparison, 98 subjects were randomly divided into two groups:experiment group in which the toothpaste containing NovaMin was used, and control group in which the toothpaste without NovaMin was used. Visual analog scale scoring was used to evaluate the degree of sensitivity to air stimulus respectively before and 4 weeks after al ergy experiment.
RESULTS AND CONCLUSION:Total y 88 patients completed the experiment. After treatment with toothpaste for 4 weeks, visual analog scale scores in the experiment group decreased from 4.25±1.87 at baseline to 2.53±1.22 by air stimulus, and visual analog scale scores in the control group decreased from 4.03±1.92 at baseline to 3.63±1.45. The visual analog scale scores in the experiment group and control group both reduced, and the difference was with statistics significance (P<0.05). Compared with the control group, visual analog scale scores in the experiment group decreased more significantly. It showed that the toothpaste containing NovaMin has significant effect on dentin hypersensitivity after subgingival scaling and root planing surgery.

Objective To evaluate the imaging performance and characteristics of peripheral primitive neuroectodermal tumors (pPNET), in order to raise awareness of the disease and the diagnostic accuracy. Methods Thirteen patients with pPNET who confirmed by puncture or pathology were enrolled in this study. The CT and MRI features were retrospectively analyzed. Four patients received simple routine CT examination, and 9 patients had MRI examination based on X-ray, CT examination. Results The part of body involved was more widely.Two patients occurred in the sinuses, 1 patient in the chest wall, 1 patient in the lung, and 3 patients in the abdominal and pelvic(1 patient involved the pelvic floor through the pelvic wall lesions to basins), 1 patient in the spine, and 5 patients located in the extremities. The characteristics of pPNET by CT and MRI in soft tissue of 8 patients showed single large soft tissue mass, and the biggest was 11.2 cm × 10.6 cm. In bonds and joints of 5 patients, CT and MRI showed wide range of soft tissue mass, mixed internal signal/density with obviously uneven enhancement, significant bone destruction and dissolvable osseous changes, and no obvious tumor bone and calcification. Conclusions Each site has its relative imaging characteristics of pPNET. CT and MRI can show lesions involving the scope, internal structure, with or without adjacent tissue invasion and metastasis, and provide guidance for clinical treatment and selecting treatment regimen. But in the end, it depends on the diagnosis of pathological and immunohistochemical examination.

Objective: To evaluate the value of MRI-T₂WI texture analysis in the differentiation of atypical medulloblastoma and ependymoma of the fourth ventricle. Methods: Preoperative MRI data of 36 cases of fourth ventricle tumor (19 cases of medulloblastoma and 17 cases of ependymoma) confirmed by the Central Theater General Hospital of the Chinese People′s Liberation Army were retrospectively analyzed. Manually sketch areas of interest (ROI) were made using texture analysis software to get histogram parameters, including mean, median, standard deviation, skewness, kurtosis, maximum, minimum, heterogeneity, entropy, the 5th percentile (T₂WI_5th), the 10th percentile (T₂WI_10th), the 25th percentile (T₂WI_25th), the 50th percentile (T₂WI_50th), the 75th percentile(T₂WI_75th), the 95th percentile(T₂WI_95th). Independent sample t test or mann-whitney U test was used for statistical analysis of each parameter value between the two groups. Logistic regression analysis was used to perform multiparameter joint analysis on meaningful parameters. The area under the curve (AUC) was obtained by using the subject operating characteristic (ROC) curve to determine the threshold and diagnostic efficacy for distinguishing the two group. Results: The mean, median, T₂WI_5th, T₂WI_10th, T₂WI_25th, T₂WI_50th, T₂WI₇5th values of the medulloblastoma group were smaller than those of the ependymoma group, and difference was statistically significant (P<0.05). The T₂WI_5th had the best diagnostic performance. When the critical value was 1 343, the diagnostic specificity was 75.0% and the sensitivity was 92.9%. Logistic regression was used to predict the joint analysis of probability parameters. T₂WI_5th+T₂WI_10th had the best performance, and AUC was 0.928. When the critical value was 0.75, the diagnostic specificity was 75.0% and the sensitivity was 100.0%. Conclusions MRI-T₂WI texture analysis can provide quantitative information for preoperative diagnosis of atypical medulloblastoma and ependymoma and improve the accuracy of preoperative diagnosis, which has obvious clinical value.

The interventional therapy of vascular stent implantation is a popular treatment method for cardiovascular stenosis and blockage. However, traditional stent manufacturing methods such as laser cutting are complex and cannot easily manufacture complex structures such as bifurcated stents, while three-dimensional (3D) printing technology provides a new method for manufacturing stents with complex structure and personalized designs. In this paper, a cardiovascular stent was designed, and printed using selective laser melting technology and 316L stainless steel powder of 0-10 µm size. Electrolytic polishing was performed to improve the surface quality of the printed vascular stent, and the expansion behavior of the polished stent was assessed by balloon inflation. The results showed that the newly designed cardiovascular stent could be manufactured by 3D printing technology. Electrolytic polishing removed the attached powder and reduced the surface roughness Ra from 1.36 µm to 0.82 µm. The axial shortening rate of the polished bracket was 4.23% when the outside diameter was expanded from 2.42 mm to 3.63 mm under the pressure of the balloon, and the radial rebound rate was 2.48% after unloading. The radial force of polished stent was 8.32 N. The 3D printed vascular stent can remove the surface powder through electrolytic polishing to improve the surface quality, and show good dilatation performance and radial support performance, which provides a reference for the practical application of 3D printed vascular stent.
Humans ; Stainless Steel ; Powders ; Cardiovascular System ; Constriction, Pathologic