BACKGROUND: The filling compactness can not be guaranteed due to apparatus retention in traditional lateral condensation.The warm gutter filling can achieve good results because of the easy changeable of gutta-percha in softening states.OBJECTIVE: To compare the warm gutta-percha fillings (Obtura Ⅱ and BeeFill 2 in1 filling) and cold lateral compacted gutta-percha with the bypassing root canal preparation in the intracanal separated instrument of oval canal.METHODS: Firstlythe 60 oval root canals of fiat mandibular central incisors were randomly divided into three groups, with 20 teeth in each group. After that, the root canal was filled with BeeFill 2 in1, Obtura Ⅱ condensation, and lateral condensation.The percentage of void at 5-mm to root tip versus cress section area was observed under a scanning electron microscope.RESULTS AND CONCLUSION: Under in vitro condition, the difference of percentage of void area versus root canal area between the Obtura Ⅱ condensation group and the lateral condensation group had significance (P=0.013), and the similar difference could be found between the BeeFill 2 in1 condensation group and the lateral condensation group (P=0.014), but the difference had no significance between the BeeFill 2 in1 condensation group and the Obtura Ⅱ condensation group (P=0.088).The results revealed that the root canal can be sealed accurately when establish hypass root next to the separated instrument and filled with BeeFill 2 in1 warm gutter filling.

BACKGROUND:Obturation with warm gutta-percha can achieve perfect three-dimensional root canal obturation effect. Due to specific structure of oval canal, particularly in the bypass preparation process, excessive cutting of local tooth tissue may lead to tooth tissue thinning and irregular shape. The separation equipment is the metal with good heat conduction, so the heat caused by the bypassing warm gutta-percha obturation would burn periodontal tissue remains controversial. OBJECTIVE:To investigate the changes of root surface temperature produced by two bypassing warm gutta-percha obturation for the separation instrument in oval canalin vitro by using infrared thermography. METHODS:Forty mandibular first premolars were harvested from oval canals, and were separated using stainless steel 15# K file at apical 3 mm, with the length of 3 mm. The root canal bypassing was prepared using TF nickel-titanium file under operating microscope. The teeth were randomly divided into two groups, with 20 teeth in each group, and were obturated with the Thermafil warm gutter-percha and E&Q plus warm gutta-percha vertical compaction, respectively. An infrared thermoviewer was used to measure the external root surface temperature before and after the obturation. RESULTS AND CONCLUSION:Two warm gutta-percha obturation methods used for separating instruments bypassing in the oval root canal, had both caused the rise of root surface temperature, which was less than 10℃. In the Thermafil group, the temperature changes were 3.2-8.1℃ and the average change was 4.97℃. In the vertical condensation group, the temperature changes were 5.5-9.8℃ and the average change was 7.35℃. There were significant differences in the change of root surface temperature between the two groups (P < 0.05). Thermafil warm gutter-percha obturation would increase the root surface temperature, but cannot damage periodontal tissues. It is more secure than warm gutta-percha vertical condensation.

BACKGROUND:Due to the complexity and irregularity of bypass obturation of oval root canal and the particular stress of the post and core to the tooth, we have not yet found a reasonable post crown for dental restoration after bypass obturation of the oval root canal.
OBJECTIVE:To compare the flexural capacity of the three kinds of post-and-core repair systems (cobalt-chromium cast post and core, zirconium oxide post and core, and CAD/CAM-fabricated glass fiber post and core) after bypass obturation of the oval root canal warm gutta.
METHODS: Ninety mandibular first premolars were selected for bypass obturation of the root canal with Obtura II & System B, and then randomized into three groups that were respectively restored with cobalt-chromium cast post and core, zirconium oxide post and core and CAD/CAM-fabricated glass fiber post and core. After that, cobalt-chromium metal crown was used for ful-crown restoration. Fracture strength and fracture type were recorded in different groups.
RESULTS AND CONCLUSION: The fracture resistance was higher in the cobalt-chromium cast post and core group and zirconium oxide post and core group than the glass fiber post and core group (P < 0.05), and the former two groups had no significant difference. Cobalt-chromium cast post and core was fractured at the root of tooth, and could not be repaired; the zirconium oxide post and core was fractured at the root neck and root of tooth, which was confirmed as reparative fracture; the glass fiber post and core was fractured at the tooth neck, which could be restored. These findings indicate that the cobalt-chromium cast post and core can bear greater occlusal force, but has a higher probability of root fracture; the CAD/CAM-fabricated glass fiber post and core exhibits a lower probability of root fracture

BACKGROUND:Stem cels from the apical papila are a new kind of mesenchymal stem cels, and whether it can
be used in root regeneration is the key to the present study. OBJECTIVE:To culture rat stem cels from the apical papila and periodontal ligament stem celsin vitro, and to compare the biology behaviors of these two kinds of cels, thereby providing experimental basis for the application of stem cels from the apical papila in root regeneration. METHODS:The apical papila, as wel as the periodontal ligament tissues from the healthy mandibular teeth of young rats were digested and cultured. Immunophenotypes of stem cels from the apical papila and periodontal ligament stem cels were detected by immunofluorescence technique. Then, cel growth curves were determined by MTT method and mineralized nodule formation was observed by alizarin red staining. RESULTS AND CONCLUSION:Stem cels from the apical papila and periodontal ligament stem cels were both positive for STRO-1. Stem cels from the apical papila were positive for CD90 and weakly positive for CD146. Periodontal ligament stem cels were positive for CD146 and weakly positive for CD90. The absorbance values of stem cels from the apical papila and periodontal ligament stem cels increased with the increasing of time and became stable at 8 days. Since the 4th day, the proliferation capacity of stem cels from the apical papila was significantly stronger than that of periodontal ligament stem cels (P < 0.05). Both of stem cels are visible to have mineralized nodule formation. Compared with the periodontal ligament stem cels, stem cels from the apical papila were stained obviously deeper and had more mineralized nodules. These results show that stem cels from the apical papila have stronger proliferation capacity and mineralization ability than periodontal ligament stem cels. Cite this article:Zhao L, Yu L, Yuan P, Zhou CM, Wu PL.Stem cels from the apical papila versus periodontal ligament stem cels: biological behaviors. Zhongguo Zuzhi Gongcheng Yanjiu. 2016;20(1):113-117.

Objective To improve the satisfactory rate of patients by using the full responsibility gradation nursing pattern.Methods Reforming the nursing scheduling and diminishing the nursing unit to assure the patients could acquire the continuous and stable nursing service when they were in the hospital.Results The ratio of patients can recognize their nurses were from 31.71% to 76.14% after using the nursing intervention,P

BACKGROUND:The periodontal ligament stem cels can promote periodontal tissue regeneration, providing a new way for the treatment of periodontitis. OBJECTIVE:To observe the inflammatory microenvironment effects on the biological properties of periodontal ligament stem cels. METHODS: Periodontal ligament stem cels from healthy controls and patients with periodontitis were primarily cultured by tissue digestion method, purified using limited dilution method, and identified through detection of CD146 and STRO-1. Then, passage 3 cels were taken and denoted as normal control and inflammation groups folowed by osteogenic induction. RESULTS AND CONCLUSION:Purified cels from two sources both expressed STRO-1 and CD146. Periodontal ligament stem cels in the inflammation group showed higher multiplication capacity, but the osteogenesis ability was lower compared with the normal control group. The expressions of Runx2 mRNA and Osterix mRNA were dropped significantly after the stimulus of tumor necrosis factor-α (P < 0.05), but the interleukin-1β and interleukin-6 did not have a significant impact. Tumor necrosis factor-α at 0.1 and 1 μg/L had no significant effects on the expression of Runx2 mRNA, but the expression of Runx2 mRNA was decreased significantly after treatment with 10 μg/L tumor necrosis factor-α (P< 0.05). It is confirmed that the molecular signaling mechanism inside the periodontal ligament stem cels is changed under inflammatory microenvironment, so that the differentiation capacity of cels from the inflammatory sources is lowered. Moreover, tumor necrosis factor-α is one of the key factors and its optimalconcentration is 10 μg/L.

OBJECTIVEWe explored the expressions of the Notch and Wnt signaling pathways and their significance in the repair process of alveolar bone defects by establishing animal models with a composite of autologous bone marrow mesenchymal stem cells (BMSCs) and platelet-rich fibrin (PRF) to repair bone defects in the extraction sockets of rabbits.

METHODSA total of 36 two-month-old male New Zealand white rabbits were randomly divided into four groups, and the left mandibular incisors of all the rabbits were subjected to minimally invasive removalunder general anesthesia. BMSC-PRF compounds, single PRF, and single BMSC were implanted in Groups A, B, and C. No material was implanted in Group D (blank control). The animals were sacrificed at 4, 8 and 12 weeks after surgery, the bone defect was immediately drawn, and the bone specimens underwent surgery after four, eight, and twelve weeks, with three rabbits per time point. The expressions of Notch1 and Wnt3a in the repair process of the bone defect were measured via immunohistochemical and immunofluorescence detection.

RESULTSImmunohistochemistry showed that the expressions of Notch1 and Wnt3a in Groups A, B, and C were higher than that in Group D at the fourth and eighth week after operation (P<0.05). By contrast, the expressions of Notch1 and Wnt3a in Group D were higher than those in Groups A, B, and C at the twelfth week (P<0.05). Immunofluorescence showed that the expressions of both Notch1 and Wnt3a reached their peaks in the new bone cells of the bone defect after four weeks following surgery and gradually disappeared when the bone was repaired completely.

CONCLUSIONNotch1 and Wnt3a signaling molecules are expressed in the process of repairing bone defects using BMSC-PRF composites and can accelerate the healing by regulating the proliferation and differentiation of BMSCs. Moreover, the expressions of Notch and Wnt are similar, and a crosstalk between them may exist it.

Alveolar Bone Grafting ; methods ; Animals ; Blood Platelets ; Bone Marrow Cells ; cytology ; Bone Transplantation ; methods ; Bone and Bones ; abnormalities ; Cell Differentiation ; Fibrin ; administration & dosage ; Male ; Mesenchymal Stem Cell Transplantation ; methods ; Mesenchymal Stromal Cells ; Platelet-Rich Plasma ; Rabbits ; Random Allocation ; Receptor, Notch1 ; metabolism ; Tissue Engineering ; Wnt Signaling Pathway ; Wnt3A Protein ; metabolism ; Wound Healing

BACKGROUND: Increasing attention has been paid to vascular components of the adipose-derived matrix and adipose-derived stem cells in tissue engineering. Existing methods for separating the vascular components of the adipose-derived matrix mainly include enzymatic and bolus injection, both of which have fatal disadvantages. OBJECTIVE: To search for a method for preparing adipose-derived stromal vascular fractions with high efficiency, safety, and simplicity. METHODS: The group without any treatment was used as the negative control, and the enzymatic hydrolysis method served as the positive control. The enzymatic hydrolysis method, traditional bolus method, modified bolus method, glass beads method and built-in ultrasonic waves method were compared through cell volume, survival rate, cell fragments, cell viability, increment rate and detection of microbial infection. The enzymatic hydrolysis method and the common bolus injection method were commonly used in the separation of vascular component cells of the fat source matrix; the improved bolus method was a method obtained by improving on the basis of the ordinary bolus method; the glass bead method was to use the glass bead to oscillate. The shear force generated was obtained by adding glass beads to the fat granules and shaking at 2 500 r/min for 9 minutes to prepare stromal vascular fraction cells. Using the built-in ultrasonic method, adipose tissue was treated at 25 W for 36 seconds to obtain stromal vascular fraction cells through a cavitation effect. RESULTS AND CONCLUSION: (1) The size of stromal vascular fraction cells isolated by five methods showed no significant difference (P > 0.05). (2)The cell viability was lowest in the negative control group, and highest in the enzymatic hydrolysis group. The cell viability in the enzymatic hydrolysis, glass bead, and built-in ultrasonic wave groups was significantly higher than that in the modified and traditional bolus groups (P < 0.05). (3) The cell survival rate and cell proliferation rate in the enzymatic hydrolysis, glass bead, and built-in ultrasonic wave groups were significantly higher than those in the modified and traditional bolus groups (P < 0.05). (4) The cell fragmentation rate and cell apoptosis rate in the enzymatic hydrolysis, glass bead, and built-in ultrasonic wave groups were significantly lower than those in the modified and traditional bolus groups (P < 0.05). (5) These results indicate that the built-in ultrasonic method and the glass bead method are better in enriching vascular components of the adipose-derived matrix. But glass bead method adds exogenous products, so it increases the risk of pollution. Built-in ultrasonic method inserts the ultrasound probe into the adipose tissue, but as long as the ultrasound probe is thoroughly sterilized, the risk of contamination is minimized. In general, the built-in ultrasonic method and the glass bead method are superior to modified and traditional bolus methods.

Objective To explore the value of cMRI and MRS in diagnosis and differential diagnosis of single brain metastases and localized high grade gliomas.Methods The cMRI (T1WI,T2WI and contrast-enhanced MRI)and MRS data of 23 cases with single brain metastases and in 28 cases with high grade gliomas confirmed by pathology were collected and analyzed retrospectively.Results cMRI:①There were no significant differences of T1WI,T2WI and constrast-enhanced MRI between single brain metastases and high-grade gliomas.②Enhanced images of single brain metastases and localized high-grade gliomas showed that there was a significant difference in the peritumoral edema area:the nodular or ring enhancement were found in single brain metastases,the outer outline of ring enhancement was smooth,and there was no enhancement at the peripheral edema area;Irregular patchy or ring enhancement were found in localized high-grade glioma tumor,both of the outer and inner edges of the ring enhancement rough,a little patchy enhancement at the peripheral edema area were found in 1 6 patients,and there was no enhancement of the edema area in the other 1 2 patients.MRS:①There were no significant differences of the tumor parenchyma in the peaks of NAA,Cr,Cho and central Lac between single brain metastases and localized high grade gliomas.②A significant difference of the peripheral edema area were observed between them.The peaks of NAA,Cr,Cho at the edema area in all single brain metastases patients were normal.But in all high-grade glioma patients,the NAA and Cr peaks were decreased,while the Cho peaks were increased.Conclusion The morphological manifestations of single brain metastases are similar to localized high grade gliomas.An obvious difference of cMRI and MRS lines exists in the peritumoral edema area between them,which could be used for differential diagnosis.

ObjectiveTo investigate the clinical and prognostic features of hypertriglyceridemic pancreatitis (HTGP) during pregnancy. MethodsA total of 77 patients with acute pancreatitis in pregnancy who were admitted to The Affiliated Hospital of Southwest Medical University from January 2013 to June 2020 were enrolled as subjects, and according to the presence or absence of HTGP, they were divided into HTGP group with 38 patients and non-HTGP group with 39 patients. The two groups were compared in terms of the clinical features including age, pregnancy, laboratory markers, complication, and prognostic indices. The independent samples t-test was used for comparison of normally distributed continuous data between two groups, and the Mann-Whitney U test was used for comparison of non-normally distributed continuous data between two groups; the chi-square test or the Fisher’s exact test was used for comparison of categorical data between two groups, and the Mann-Whitney U test was used for comparison of ranked data between two groups. According to the trimester of pregnancy, the patients were divided into early pregnancy group with 4 patients, middle pregnancy group with 14 patients, and late pregnancy with 59 patients, and blood lipid levels were compared between groups; the Kruskal-Wallis H test was used for comparison between two groups or within each group. ResultsCompared with the non-HTGP group, the HTGP group had significantly higher mean age (t=-3.000, P=0.004) and proportion of patients with diabetes (χ2=8.867, P=0.003). Compared with the non-HTGP group, the HTGP group had a significantly higher proportion of patients with disease onset in the third trimester (P＜0.001) and a significantly lower serum level of sodium (Z=-6.328, P＜0.001). Compared with the non-HTGP group, the HTGP group had significantly higher incidence rates of acute peripancreatic fluid collection (76.3% vs 33.3%, χ2=14.342, P＜0.001) and systemic inflammatory response syndrome (81.6% vs 410%, χ2=13.310, P＜0.001). There were significant differences between the two groups in the length of hospital stay, the rate of admission to the intensive care unit, and hospital costs (Z=-2.077, χ2=11.537, Z=-3.525, all P＜0.05). The levels of total cholesterol and triglyceride in the third trimester were significantly higher than those in middle pregnancy (both P＜0.05). ConclusionCompared with the non-HTGP group, the HTGP group has a higher proportion of patients with disease onset in the third trimester of pregnancy, a higher risk of complications, a longer length of hospital stay, and higher hospital costs.