Objective:To combine the cold lateral condensation with System B root canal filling techniques in order to increase the amount of gutta-percha to fit different canal that could improve percentage of gutta-percha-filled area(PGFA)and decrease the probability of apical extrusion. Methods: Two groups of extracted human canines (total 80) were prepared by modified double-flared technique and filled with gutta-percha by System B technique and the combined technique respectively. The overfilling samples were collected. A horizontal section was cut 1.5 mm from the apical foramen of each tooth. The cross-sectional area of the canal and the gutta-percha was measured using an image-analysis program. The PGFA was then calculated. Results:Overfilling rate in the combined technique group was significantly lower than that of the control group (P

Objective The aim of the study was to analyse the middle ear function of one hundred and twenty-five newborns using 226,678,1 000 Hz tympanometry. Methods Tympanometries with 226,678,1 000 Hz probe tones were obtained from 125 newborns (250 ears) by means of GSI Tympstar middle ear analyzer. The newborns with abnormal tympanograms were referred for temporale CT. Results One case of 226 Hz tympanograms was type "As" while others were all type "A",of which single-peaked tympanograms was 43.2%(108/250),W-shaped tympanograms was 56.8%(142/250). The abnormal pattern of 678 Hz tympanograms were 74 ears,and the abnormal pattern of 1 000 Hz tympanograms were 35 ears. 43 newborns (86 ears) have accepted temporale CT and results showed 30 middle ears with effusion. Conclusion 226 Hz probe tone tympanometry couldn't reflect the middle ear function of newborns. The sensitivity of 678 Hz probe tone tympanometry in the diagnosis of middle ear function of newborns was good,but specificity was worse. The sensitivity and specificity of 1 000 Hz probe tone tympanometry were the best.

Objective To study the effects of multi frequency tympanometry and acoustic stapedius reflexes on the diagnosis of the middle ear functions of infants.Methods Tympanometries with 226,678 and 1 000 Hz probe tones and 500 and 1 000 Hz acoustic stapedius reflexes were performed on infants at age 0~1 year.128 normal infants(256 ears) and 104 abnormal infants(168 ears) were tested with GSI Tympstar middle ear analyzer.Results The patterns of 226 Hz tympanograms were non-peaked,single-peaked and W-shaped.There were no significant differences between two groups of infants aged 0～6 months.The patterns of 678 Hz and 1 000 Hz tympanograms showed significant differences between two groups of infants aged 0～1 year.The outcomes of 500 Hz and 1 000 Hz acoustic stapedius reflexes showed no differences between the same age groups.There were significant differences between normal group and abnormal group.Conclusion Tympanometry with 678 Hz and 1 000 Hz probe tones can yield accurate diagnostic results in the assessment of the middle ear functions for infants younger than six months.The tympanometry with three frequency probe tones is sensitive to infants aged 6～12 months.The outcomes of acoustic stapedius reflexes at 500 and 1 000 Hz show no differences between the same age groups,but presences become more noticeable as a function of ages.

Objective:To compare quantitatively the quality of the canal isthmus retropreparation among three kinds of ultrasonic ret-rotips.Methods:1 20 maxillary bicuspid teeth with two canals and an isthmus were randomly assigned to 3 groups(n=40).The canal isthmus retropreparation were made respectively using ultrasonic niti tip RE2,diamond tip Berutti and #25K file.Image processing and analysis system were used to measure the preoperative and postoperative parameters for further evaluation.Results:The cutting volume of ultrasonic niti tip RE2 group was significantly less than those of other two groups(P<0.05).Conclusion:Ultrasonic niti tip RE2 is feasible in the canal isthmus retropreparation.

Objective:To examine the surface of mineral trioxide aggr eg ate (MTA) when treated in different conditions in vitro. Method: Root blocks were prepared. MTA and other three dental materials (Dycal, Dyr act and amalgam) were respectively filled into the root canals of prepared root blocks. The roots with the materials were maintained in distilled water or simul ated body fluid (SBF) at 37 ℃ for 5 days. Scanning electron microscopy(SEM) and X-ray energy dispersive spectroscopy(EDS) were employed to investigate the mor phological changes and chemical components. Results:There was pr ecipitate of simple crystal units or crystalline structure in the MTA specimens. EDS showed one or two peaks corresponding to calcium or calcium and phosphorus. Conclusions:Apatite may produce and grew by MTA on its surface.

Objective To investigate the effect of warfarin on coagulation function and hemorheology index in patients with atrial fibrillation. Methods Retrospective a total of 90 patients with atrial fibrillation who underwent anticoagulant therapy from June 2014 to December 2015 in The Fourth People's Hospital of Wenling City were randomly divided into the control group and the warfarin group with 45 cases in each group.The patients in the control group were treated with aspirin, the patients in the warfarin group were treated with warfarin.The indexes of coagulation function and hemorheology were measured before and after treatment, and the effects of warfarin on patients with atrial fibrillation were observed and analyzed. Results After treatment, there was no significant change in coagulation function in the control group, the thrombin time (PT), thrombin time (TT), and partially activated thrombin time (APTT) of warfarin group were significantly increased, the difference was statistically significant (P<0.05), and the coagulation function of warfarin group was significantly higher than that of the control group, the difference was statistically significant (P<0.05).The plasma viscosity, red blood cell index, high shear whole blood viscosity, low shear whole blood viscosity and fibrinogen (FIB) were significantly lower in the two groups, the difference was statistically significant (P<0.05), and the high shear whole blood viscosity, low shear whole blood viscosity and FIB of warfarin group were significantly lower than those of the control group, the difference was statistically significant ( P <0.05 ). Conclusion Warfarin has a potent effect on platelet activation, which can produce anticoagulation by adjusting coagulation function, platelet parameters and hemorheology in patients with atrial fibrillation.

Objective: To eliminate the noise of the plethysmography wave and obtain plethysmography wave signal without noise. Methods:Using sym4 and combining the improved wavelet threshold wavelet algorithm to remove high frequency white noise of plethysmography wave, and then using spline differential fitting method to remove baseline drift of pulse wave volume. Results:The experimental results show that the high frequency noise and baseline drift of plethysmography wave have been removed effectively processed by the sym4 wavelet and combining with improved threshold of wavelet algorithm and spline difference after fitting. Conclusion:The method can well remove the noise of the plethysmography wave and retains the effective information of plethysmography wave effectively.

ObjectiveTo observe the therapeutic effect of early comprehensive rehabilitation and the value of intensity time (I/t) curve examine for peripheral facial paralysis.Methods89 patients with peripheral facial paralysis were treated by early comprehensive rehabilitation program in 1 week and were examined by I/t curve in 10～20 days.ResultsThe rate of the cure and excellent was 93.26%.Normal nerve detected by I/t curve were 62.92% and partial denervation were 37.08%.ConclusionPatients with peripheral facial paralysis who were treated by early comprehensive rehabilitation will have good prognosis. As a kind of examine ways, I/t curve can be used in clinic.

Objective To investigate the antimicrobial resistance proifle of Shigella flexneri in Shanghai from 2010 to 2014 and examine the mechanism of fluoroquinolone resistance.Methods Kirby-Bauer method was used to determine the susceptibility of the S. flexneri strains to 14 antibiotics. The minimum inhibitory concentration (MIC) of ciprofloxacin was tested by E-test. Mutations within quinolone resistance determining regions (QRDR) of gyrA and parC and plasmid-mediated quinolone resistance (PMQR) genes,qnrA,qnrB,qnrS andaac(6')-Ib-crwere identified by polymerase chain reaction (PCR). All the products were subjected to sequencing analysis.Results More than 90 % of the 139S. flexneri isolates were resistant to ampicillin, streptomycin, tetracycline, and nalidixic acid, 40.3 % to ciprofloxacin and 30.2 % to cefepime, respectively. Genetic mutation of gyrA and parC was found in 98.6 % and 97.8 % of the strains, respectively. Three point mutations (Ser83, Asp87 and His211) were detected in gene gyrA and one point mutation (Ser80) was found in in gene parC. Plasmid-mediated resistant gene qnrS was found in 9 strains and aac(6')-Ib-cr in 6 strains.Conclusions The antibiotic resistance of S. flexneri is serious in Shanghai. The mutation rate within QRDR is high. Point mutation in Asp87 of gyrA is the main mechanism of quinolone resistance. The plasmid-mediated quinolone-resistant genes also play an important supplementary role.

Objective:To compare the quality of root-end preparation quantitatively between ultrasonic retrotips and traditional slow-speed handpiece. Methods: 27 maxillary second bicuspid teeth with two canals and an isthmus were randomly assigned to 3 groups.Root-end preparations were made respectively using ultrasonic diamond tip Berutti and niti tip RE2, ultrasonic 40~#K file and slow-speed handpiece with No.2 round bur. Image processing and analysis system were used to measure the preoperation and postoperation parameters for further evaluating the difference between the two techniques. Results: The cutting volume of ultrasonic instruments was less than slow-speed handpiece(P<0.000 1). Conclusion: Ultrasonic instrument is better in the root-end preparation than traditional slow-speed handpiece.