OBJECTIVETo evaluate the influence of eugenol-containing and resin-containing endodontic sealers on the bond strength of fiber posts using different strategies of root canal irrigation.

METHODSForty-eight mandibular premolars were endodontically treated. The specimens were randomly assigned into two groups according to different endodontic sealers. Group A used Endofil (eugenol-containing endodontic sealer), and group B used AH-plus (resin-containing endodontic sealer). After post space preparation, each group was randomly assigned into three subgroups according to the strategies of root canal irrigation (eight premolars in each subgroup). Group Al and B1: 0.9%NaCl irrigation; Group A2 and B2: 17% ethylene diamine tetraacetic acid (EDTA)+5.25%NaClO+0.9%NaCl irrigation; Group A3 and B3: ultrasonic agitation associated with 1 7%EDTA+5.25%NaClO+0.9%NaCl. One week after the cementation of fiber posts using RelyX™ Unicem, a push-out test was performed to measure the bond strength of the posts. The microstructure of the root canal surface was examined under scanning electron microscope (SEM).

RESULTSThe bond strengths of the six groups were as follows: Al (7.96±2.23) MPa, A2 (9.95±2.89) MPa, A3 (18.88±3.69) MPa, B1 (11.41±3.71) MPa, B2 (14.00±4.04) MPa, and B3 (19.14±3.27) MPa. Statistical analysis revealed a significant interaction between the different endodontic sealers and the strategies of root canal irrigation (P<0.05). Lower bond strength was found in group Al but not in group BI (P<0.05), and the same result was revealed when comparing group A2 and B2. No significant difference was observed between group A3 and B3 (P>0.05). SEM showed that the root canal in group A3 and B3 achieved the cleanest surface with nearly all dentine tubules opened.

CONCLUSIONThe eugenol-containing endodontic sealer can impair the bond strength of fiber posts compared with the resin-containing sealer when the root canal is irrigated by 0.9% NaCl or 17%EDTA+5.25%NaClO+0.9%NaC. No difference was observed between the two sealers when using 17%EDTA+5.25% NaCIO+0.9%NaCl combined with ultrasonic irrigation.

Bicuspid ; Cementation ; Dental Bonding ; Dental Pulp Cavity ; Dental Stress Analysis ; Dentin ; Humans ; Post and Core Technique ; Root Canal Filling Materials ; Root Canal Irrigants ; Root Canal Therapy

OBJECTIVETo evaluate the effect of different auxiliary resistance forms on the resistance and marginal fitness of complete crowns for short molar preparations.

METHODSA total of 70 Nissin resin teeth were prepared with 20° total occlusal convergence, 2.5 mm of occlusocervical height, and a shallow finish line on a milling machine. The milled preparations were then randomly assigned to 7 groups of 10. The first group was used as the control group. A total of 30 dies were modified by preparing interproximal grooves with angles of 0°, 6°, and 20° centered on the mesial and distal surfaces of the dies. The rest of the teeth were prepared with occlusal holes in the center of the occlusal surface milled with the same burs to form 0°, 6°, and 20° holes. Cobalt-chromium copings were fabricated for all specimens. The marginal gap of specific points on the axial surface was measured before and after cementation. The resistance of each specimen was evaluated by applying an external force at an angle of 45° to the long axis of the die by using a universal testing machine in a lingual to buccal direction. The maximum force applied before crown dislodgement was measured. Data were analyzed using the SAS 9.2 software.

RESULTSThe results showed that the 0° groove, 0° hole, and 6° hole were effective in improving the resistance of the complete crowns (P<0.05). The 0° groove, 6° groove, 0° hole, 6° hole, and 20° hole had significant difference with the control group in terms of marginal discrepancies (P<0.05).

CONCLUSIONAuxiliary resistance forms with less degree indicate greater resistance force but worse marginal fitness. In clinical practice, if the resistance of a preparation is enough, the auxiliary resistance forms should be avoided from being used.

Cementation ; Crowns ; Dental Prosthesis Design ; Dental Prosthesis Retention ; Humans ; Molar ; Tooth Crown

Objective To construct the prokaryotic expression vector bearing fusion gene NT4-ADNF-9 and lay foundation for further study on genetic therapy of neuraseusory deafness. Methods By means of asymmetrical prince/ template, double stranded eDNA of activity dependent neurotrophic factor-9 (ADNF-9) was obtained, which included restriction enzymes sites on the two extremities. ADNF-9 eDNA was ligated to the signal and leader peptides of nenrotrophin 4 (NT4), and the fusion gene was named NT4-ADNF-9. Then it was suheluned into prokaryotic expression vector pBV220, and called pBV220/ NT4-ADNF-9. Results Evidences of DNA sequence analysis and restrtction enzymes digestion showed that we recombined ADNF-9 eDNA to the 3'terminal of the signal and leader peptides of NT4, and the fusion gene was subcluned into pBV220 successfully. Bioactivity of the products was proved that it could support the cell survival and neurite growth in the primary cultures of dorsal root ganglia (DRG) of embryonic day-8 cbicken neurons as compared to the control. Conclusion Prokaryotic expression vector pBV220/NT4-ADNF-9 can be constructed successfully and the bioactivtty is satisfactory.

Objective To prepare a kind of new lipid perfluorooctylbromide(PFOB) nanoparticles and to explore its potential application as an ultrasound contrast agent. Methods Lipid PFOB nanoparticles were prepared by microfluidization techniques. The morphology and distribution were observed with optical microscope and transmission electron microscope. Particle size and electric potential were determined with Malvern laser light scattering analyzer. Twelve normal Wistar rats were performed directly contrast imaging after injection of PFOB nanoparticles via caudal vein. Vital signs of the rats were monitored during the whole study. And eehogenie intensity of the liver was dynamically quantified through DFY ultrasound quantified analysis system. The mechanism of enhancement was studied by the frozen sections of rat's liver and spleen. Results The nanoparticles size and distribution were highly uniformed. The grey scale ultrasound imaging of the rat's liver and spleen were enhanced by PFOB nanoparticles. Ten seconds after PFOB nanoparticles injected,enhancement of liver began, the peak time was approximately 3 - 4 min, the duration of contrast enhancement was nearly up to 1 h, The enhancement of spleen was more significant and the duration was much longer. No abnormal changes of the rat's vital signs appeared during the study. Frozen sections suggested that PFOB nanoparticles accumulated in the liver and spleen was the potential mechanism of enhancement. Conclusions This novel and safe lipid PFOB nanoparticles could make prolonged enhancement of rat's liver and spleen,which has a good potency for ultrasound application.

Objective To realize medical information collection and digital management in field battle and the fundamental information and cure of medical staff of emergency medical, equipment and the wounded were included in it. Methods The collecting information were transmitted to computer through wireless connection and manage the information with Delphi7 procedure. Results The system was used firstly in large-scale practice and completed the information transcription and management on elementary and cure in hundred of wounded. Conclusion The information is up to the mustard of field and it has established base on cure information in digital management.

ObjectiveTo summarize the clinical features of ulcerative eolitis (UC) complicated by toxic megacolon for early diagnosis and proper treatment. MethodsSix cases of toxic megacolon in the patients suffered from UC in Peking Union Medical College Hospital from 1983 to 2010 were analyzed,and related literature was searched and reviewed.ResultsThe incidence of the toxic megacolon in the patients with UC in our center was 0.7％ (6/824),which was lower than those reported in the literature.There were always risk factors triggering the disease.The prognosis of the patients was poor,even after medical care and surgery intervention.Evaluation of the patients and making right timing to perform the surgery would improve the prognosis of the patients in foreign literature. ConclusionIt's crucial to make early diagnosis of the toxic megacolon in the patients suffered from UC. The right choice and timing to perform urgent surgery or selective surgery may improve their prognosis.

Superior mesenteric vein (SMV) thrombosis is a relatively rare disease. Most patients may be successfully treated with anti-coagulation alone. However, bowel stricture may develop due to intestinal ischemia which may require surgical treatment. This report describes a rare case of small bowel stricture occurring one month after successful treatment of SMV thrombosis. After segmental resection of strictured bowel, the patient's post-operative course was uneventful.

Objective To investigate and analysis the situation of malocclusion of 49 skulls of ancient resident in Xinjiang, and discuss the history evolution and the pathologic mechanism of malocclusion. Methods The investigation was carried out based on the standard of individual normal occlusion. Results Among the group of 49 skulls, the morbility rate of malocclusion was 30. 61% ; in Angle's classification of malocclution, class I was the most (73. 33%); in Mao's classification of malocclution, class I was also the most (33. 33%). Conclusion The morbility rate of malocclusion of resident in bronze age is lower than that of modern resident and nearer ages resident. There is a close releationship between the human food construction and the pathogenesis of malocclution.

Objective To collect and analyze the basic information of two dimensions electronics medicine tag, and send out the analytical information to field battle information management system and share with the resources. Methods The information were collected, analyzed and sent by adopting MC50 and some software. Results The information of collection and analysis on 80 cases was completed by the device in large-scale practice. Conclusion The device usage is convenient, the function is stable, and the rate of collection and analysis is 100%.

AIM: To study the clinical efficacy of Jinchang Capsule for the treatment of type 2 diabetes of blood-stasis syndrome. METHODS: From JAN.2001 to OCT.2004, 48 cases were divided randomly into two groups.32 cases in the treatment group were treated with oral Jinchang Capsule combined with Western medicine therapy, and 22 cases in the control group were simply treated with Western medicine therapy, with a course of 8 weeks. The changes of clinical symptoms, and fasting blood glucose (FBG), 2 h post prandial glucose(2hFBG), HbAlc, total cholesterol (Tc), triglycerides (TG), high-density lipoprotein (HDL-c), low-density lipoprotein (LDL-c) levels, and hemorheological parameters were analysed. The safety of the medicine was evaluated also. RESULTS: After treatment, the clinical symptomatic integrals were decreased remarkably in the treatment group (P0.05). There was no significant side-effect in the treatment group. CONCLUSION: The results obtained suggest that Jinchang Capsule can improve the clinical symptomatic integrals and remarkably enhance total clinical efficacy. Combining with the basic Western medicinal treatment of diabetes, it can control the obstinate hyperglycemia, and improve fat metabolism as well as bemorheological parameters. It has indicated that Jinchang Capsule has multipurpose therapeutic actions for diabetes mellitus.