Objective To detect the sealing ability of iRoot as root end retrograde filling material in vitro experiment,and to compare it with mineral trioxide aggregate(MTA) in order to provide reference basis for clinical use of iRoot.Methods The dental crown was removed in 67 single root canal anterior teeth.The routine root canal preparation and filling were performed.The root end was resected by 3 mm for conducting root end retrograde preparation.Sixty-three teeth in the samples were randomly divided into 4 experimental groups.Then the different materials were used for root end filling:iRoot BP (group A,n=17),iRoot BP plus (group B,n=17),MTA (group C,n =17),and group D(iRoot BP + gutta percha,n =12),the residual 4 samples served as the control group.The apical microleakage of 10 teeth in each experimental group was detected by the fluid dynamics.The microleakage situation at the time points of 1,7,14,28 d was observed.In addition,2 teeth selected from each group were performed the filling material ultramicrostructure observation by SEM.Each 5 teeth were remained in the group A,B and C and performed the Micro CT scanning.The porosity rate of filling material was detected.Results No obvious edge gap was found between the filling materials and dentin surface in the group A,B and D by SEM,but obvious gap could be seen in various samples of group C.Micro CT scanning found that the porosity rates in the group A,B and C were 0.020 ±0.023,0.045 ±0.035 and 0.031 ± 0.011 respectively,but showing no statistical difference(P＞0.05).The fluid dynamic experiment showed that the microleakage detection value in each group had no statistical difference(P＞0.05).Conclusion The sealing ability of iRoot and MTA used in root end retrograde sealing has no obvious difference,But iRoot operability is superior to MTA.

OBJECTIVETo explore the effect of microneedle combined with Lauromacrogol on skin capillary network.

METHODS24 male Leghone (1.5-2.0 kg in weight) were randomly divided into three groups as group A (microneedle combined with Lauromacrogol), B (microneedle combined with physiological saline) , and C(control). The cockscombs were treated. The specimens were taken on the 7th, 14th, 21th , and 28th day postoperatively. HE staining, immunohistochemical staining and special staining were performed for study of the number of capillary and collagen I/III , as well as elastic fibers.

RESULTSThe color of cockscombs in group A became lightening after treatment. The number of capillary decreased as showing by HE staining. The collagen I and III in group B was significantly different from that in group A and C (P < 0.05). Special staining showed proliferation of elastic fibers in group B.

CONCLUSIONSIt indicates that microneedle combined with Lauromacrogol could effectively reduce the capillary in cockscomb without any tissue fibrosis. Microneedle can stimulate the proliferation of elastic fiber, so as to improve the skin ageing process.

Animals ; Capillaries ; anatomy & histology ; Chickens ; Comb and Wattles ; blood supply ; drug effects ; Male ; Needles ; Polyethylene Glycols ; pharmacology ; Punctures ; instrumentation ; methods ; Random Allocation ; Skin Aging

Objective:To evaluate the accuracy and influence factors of a triple-united method used for the determination of root canal working length.Methods:Root canal working length was detemined by manual measurement,tooth average length and radiographic measurement(triple-united method).In vitro experiment was conducted in 40 teeth and clinical study in 96 teeth by experienced specialists and postgraduates.Results:The accuracy of triple-united method was 82.5% and 62.5% by spcialist and poststudents in vitro, 87.1% and 75.5% in clinic,respectively. The accuracy was interfered by experience of the examiner, tooth integrity and apical disease.Conclusion:Triple-united method can meet the clinic requirement in the determination of root canal length.

ObjectiveTo investigate DNA loads and risk factors of BK virus infection in renal transplant recipients.MethodsWe developed a real-time PCR assay to quantitate BK virus loads in 80 patients receiving renal transplantation in our center,and correlation between the BK virus load and clinical course was analyzed.BK virus loads were measured in urine and plasma. Epidemiological features and risk factors of BK virus infection were analyzed.ResultsThe positive rate of BKV viruria and viremia in 80 renal recipients was 37.5％ (30/80) and 8.75％ (7/80),respectively.BKV loads were higher in renal allograft recipients whose age was more than 50 years old.BKV loads were observed in urine and plasma (compared with group whose age was less than 50 years,P=0.017 and 0.05,respectively).BKV DNA copies were higher in group Tac than that in group CSA (P＜0.05),and the peak of BKV load in serum appeared at14th and10th month after transplantation,respectively,but the peak in urine was ahead of that in serum,appeared at 2nd and 8th month,respectively.ConclusionSerial measurement of BKV viral loads by quantitative PCR is a useful tool in monitoring the course of BK virus infection.The ages of recipients (＞50 years) and using Tac + MPA can reactivate BK virus and then result in BKVAN in renal transplant recipients. Intensive BKV monitoring is necessary for these recipients.

Objective To investigate the effects of cyclosporine on cell proliferation, apoptosis and angiogenesis of bladder cancer in rats induced with BBN.Methods Ten samples of SD rats bladder cancer induced with BBN and cyclosporine simultaneously and 10 samples of SD rats bladder cancer induced with BBN only as control were used to observe the effects of cyclosporine on cell proliferation, apoptosis and angiogenesis of bladder cancer in rats.Immunohistochemistry stain with PCNA, TUNEL and immunohistochemistry stain with CD31 were used to analyze cell proliferation,apoptosis and angiogenesis of bladder cancer in rats respectively. Results The differences of proliferation index (35.3±8.6)% and (28. 7±8.0)% respectively (P＜0.05), apoptotic index (2. 5±0.8)% and (4.3±1.3)% respectively (P＜0.05) and microvessel density 32.5±8.2 and 26.3±8.1 respectively (P＜0.05) between experimental group and control group were all significant.Conclusions Cyclosporine may stimulate the growth and development of bladder cancer through mechanisms of cell proliferation, apoptosis and angiogenesis.

OBJECTIVETo evaluate the effect of furcal perforation treated with iRoot BP.

METHODSForty newly extracted human maxillary and mandibular molars were collected. Holes in diameter of 2 mm were prepared at the roof of the central pulp cavity of 36 samples with high speed round ball diamond in order to make perforated model, and then equally and randomly divided them into two groups. The other intact four samples were used as the negative controls. In the experimental groups, group A were repaired by iRoot BP, group B were repaired by mineral trioxide aggregate(MTA). Three samples in each group were observed under scanning electron microscope(SEM), and microleakage of others was tested by measuring the concentration of leaked glucose with the enzymatic glucose oxidase-peroxidase (GOD-POD) method.

RESULTSMicroleakage of group B was higher than group A and had statistical difference (P<0.05). The dentin and iRoot BP contacted more closely in group A, some gaps existed between the dentin and MTA in group B.

CONCLUSIONFor repairing furcal perforation, the effect of iRoot BP is better than that of MTA.

Aluminum Compounds ; Calcium Compounds ; Dental Leakage ; Dental Pulp Cavity ; Dentin ; Drug Combinations ; Humans ; Molar ; Oxides ; Root Canal Filling Materials ; Silicates ; Tooth Root