The aim of this study is to evaluate the physical and mechanical properties of our homemade investment material for the IPS-Empress2 castable ceramic. The IPS specific investment material was taken as control. Results show that the setting time, density before heating, density after heating, rate of open hole, compressive strength at 2 hours after setting and the compressive strength after heating to 920 degrees C of the homemade investment material are 9 minutes, 1.813 g/cm3, 1.402 g/cm3, 38.1%, 5.42 MPa and 8.37 MPa respectively, which are comparable or even better than the specific material. Under the SEM, the crystals of the phosphate hydrate in our homemade material are smaller than those in the special material. Since the physical and mechanical properties of our homemade investment material are comparable or superior to those of the specific material, a conclusion is drawn that it has a promising prospect of future clinical application.
Aluminum Silicates ; chemistry ; Crowns ; Dental Casting Investment ; chemical synthesis ; chemistry ; Dental Materials ; chemical synthesis ; chemistry ; Dental Porcelain ; chemistry ; Lithium Compounds ; chemistry ; Microscopy, Electron, Scanning ; Shear Strength ; Surface Properties ; Tensile Strength

IPS-Empress2 is a successful all-ceramic restoration system. To lower its cost, and promote its application, a kind of homemade fast investment material has been developed. The aim of this study was to evaluate the expansion properties of this investment material. The setting expansion, thermal expansion and total expansion of the homemade fast investment material were tested. The same properties of the IPS special fast investment material were also tested as control. Then the SPSS statistics software was used to evaluate the differences between the homemade material and the special material. The results show that the setting expansion rate, thermal expansion rate and total expansion rate of the special investment material for IPS-Empress2 are 0.858%, 1.11% and 1.17% respectively, while the same parameters of the homemade investment material are 0.798%, 1.09% and 1.16% respectively. There is no statistically significant difference in these expansion properties between the two investment materials. In conclusion, the expansion properties of homemade fast investment material are comparable to those of the special fast investment material, so it can compensate for the cast contraction of IPS-Empress2 castable ceramic precisely.
Aluminum Silicates ; chemical synthesis ; chemistry ; Crowns ; Dental Materials ; chemical synthesis ; chemistry ; Dental Porcelain ; chemical synthesis ; chemistry ; Lithium Compounds ; chemical synthesis ; chemistry ; Surface Properties ; Tensile Strength

Objective To evaluate the long-term efficacy of vascularized pisiform transfer for patients with Kienb(o)ck's disease in Lichtman stages Ⅲ-Ⅳ. Methods Eleven patients were reviewed to analyze results after lunate resection and vascularized pisiform transfer for Lichtman stages Ⅲ and Ⅳ. There were six men and five women. Age ranged from 20 to 67 years with a average of 41.0±14.3 years. According to Lichtman stage. There were 4 cases in stage Ⅲa, 5 cases in stage Ⅲb, and 2 cases in stage Ⅳ. Assessment criteria included subjective assessment of pain, visual analogue scale (VAS), range of motion (ROM), grip power,Cooney wrist score and radiographic changes on each follow-up visit. The radiographic changes including pis iform bone location, shape, sclerosis change, osteoarthritis, carpal height ratio, Nattrass index, Radioscaphoid angle and ulnar variance were recorded. Results The follow-up periods of all of cases were 61-202 months,with an average of 104.1 months. Pain had improved in 10 patients and disappeared in 7 cases. The VAS score was 2.2±1.9 at follow-up visit. Range of motion of injured wristw as only 65.3% of opposite side. Grip power was 84.3% of the contralateral hand. According to Cooney score, the results were excellent in 1 case, good in 7cases, fair in 2 cases and poor in 1 case, with the excellent and good rate of 72.7%. Radiologically, 8 cases had normal position of the pisiform bone, 2 had volar displacement and 1 had ulnar displacement which leaded to widen scaphopisiform space. Six pisiform bones had normal trabecular structure, three had degenerative changes. Bone sclerosis was seen in 2 cases and osteoarthritis was found in 3 patients. Compared with radiographic parameter before surgery, carpal height ratio and Nattrass index significantly lowered and radioscaphoid angle significantly increased. Conclusion Lunate resection and vascularized pisiform transfer is an effective method for Kienb(o)k′s disease in stages Ⅲ-Ⅳ. Although carpal collapse appeared postoperatively,the results show high patient satisfaction and good function after vascularized bone transplantation.

Objective Retrospectively analyze surgical correction supracardiac total anomalous pulmonary venous con-nection (TAPVC) using sutureless technique to prevent post-repair pulmonary vein stenosis. Methods Between December 2007 and December 2008, 25 children cases of total anomalous pulmonary venous connection underwent primary surgical cor-rection. The anatomic types of TAPVC were supra cardiac in nine patients, inha cardiac in one, mixed in 3 and intra cardiac in 12. Five of nine supra cardiac TAPVC underwent correction using sutureless technique. There were 2 male and 3 female. Their age at surgeries ranged from 2 months to 13 years, and the body weight were from 4.5 kg to 2.1 kg with an average of (7.9±6.4) kg. After median sternotomy and opening the pericardium, the heart was arrested by delivering cold crystal ear-dioplegia. The heart was then positioned toward the patient' s right and under the right henri sternum. A generous incision across the posterior wall of the left atrium and one on the common pulmonary vein was made. The latter was extended upwards to the midpoint of the vertical vein. The left atrium was subsequently connected to the pulmonary venous confluence by suturing the edge of the atrium to the posterior mediastinal pericardium that surrounding the common pulmonary vein and the vertical vein with 7-0 PDS. The vertical vein was partially ligated after conclusion of CPB, leaving a diameter of 5mm shunt. Routine follow-up with echocardiogram were at diacharging, 3 months, 6 months and 1 year after surgery. Results All 5 cases survived uneventfully excopt 1 baby on ventilation over 7 days after surgery, who had bilateral lung consolidation before the operation. Echocardiogram showed satisfactory results with maxium velocity acrossing the anastomosis of 0.65 -0.85 m/s. Conclusion Sutureleas technique can avoid trauma to the pulmonary venous endothelium and minimize the tension of anastomasis. It may play an important role to prevent post-repair pulmonary vein stenosis. More patients with long-term follow-up are necessary to draw a definite conclusion of this technique.

Objective To summarize the experience and early outcomes of surgical treatment of adult tetralogy of Fallot (ATOF).Methods We retrospectively analyzed the clinical data of 227 patients with ATOF who underwent surgical repair in the Department of Cadiovascular Surgery,Guangdong Cardivascular Institute from January 2004 to December 2014.There were 112 males and 115 females at a median age of 34 years(range,18 to 58 years) and a mean weight of(49.00 ± 8.27) kg.All patients were underwent one stage repair,including 129 cases with transannular patch and 61 cases with MAPCAs in which 4 cases were underwent hybrid occlusion.Results There were 12 cases died in hospital(5.3％),24 cases with Re-thoratomy for hemaostsis,5 cases with poor wound healing,10 cases with postoperative pneumonia.There were 25 cases with residual VSD including 8 cases caused by surgeon in congenital heart disease department and 17 cases caused by surgeon in adult heart disease department(P ＜ 0.05).The repair with transannular patch required significantly longer bypass time [(87.83 ± 26.02) min vs.(78.47 ± 26.00) min,P =0.009].The cases with MAPCAs had higher cost than that with no MAPCAs [(83 137.01 ±69363.05) RMB vs.(66 184.29 ±44219.38) RMB,P=0.03].Conclusion The early outcomes of ATOF is good.The cases with MAPCAs had higher cost than that with no MAPCAs.The CHD surgeon had lower probability of residual VSD.Preoperative evaluation of MAPCAs by CHD surgeon and perioperative maintain of the right ventricular function were helpful.

Objective The results of repair for TOF with anomalous coronary artery(ACA) were studied to determine the incidence of coronary anomalies and evaluate surgical strategy choicesas well as postoperative outcomes.Methods From January 2008 to August 2014,1142 consecutive patients underwent repair of TOF including 44 patients with TOF and ACA:single coronary artery in 15,dual anterior descending coronary in 15,single left anterior descending coronary arising from the rightcoronary artery in 3 and the other ACA in 5.The median age was 5.7 years (range,1 month-27 years),and the median weight was 16.0 kg(range,4.5-51.0 kg).Surgical procedure was selected according to the extent of right ventricular outflow tract (RVOT) obstruction and distribution of the ACA.Results There was one operative death.No deaths during the follow-up period in the other 37 patients.Single patch techniquewasperformed in 15.RVOT residual obstruction detected in 7 who without transannular patch,and one need reoperation;Two patch technique was performed in 6,and 3 of them required an additional RV-PA(pulmonary artery) tube because of RVOT residual obstruction during the operation;Double oullet technique was in 6.No tube stenosis occurred in follow-up period time;PA translocation technique was in 11.The right PA stenosis was detected in 4;ACA was ligated and divided in 3,then RVOT reconstruction was performed.Conclusion The combination of ACA is not a contraindication to primary repair of TOF.But there are many anatomiacal variations of ACA,and the accuracy of preoperative diagnosis is low.So proper selection of surgical approach should be individualized based on the careful intraoperative identification of the distribution of the ACA as well as the location and degree of the RVOT obstruction.

Objective Konno-Rastan procedure is one option to cope with complex multilevel left ventricular outflow tract obstruction (LVOTO),which continues to pose a serious challenge to cardiac surgeons.The aim of this study is to retrospectively analyse indications for Konno-Rastan procedure,and to review the safeguards and pitfalls.Methods Between January 1996 and August 2012,totally 13 children with multilevel LVOTO underwent Konno-Rastan procedure.There were 8 boys and 5 girls.Age at surgeries ranged from 5 to 13 years,and weight from 12 to 51 kg with median of 21 kg.The pathology of this cohort includes:8 cases of congenital aortic valvular stenosis,3 cases of congenital aortic valvular stenosis combined with supravalvular stenosis,1 case of congenital aortic stenosis combined with VSD,coarctation and RVOT obstruction,1 case of aortic stenosis s/p percutaneous balloon aortic valvuloplasty.All patients have secondary diffuse tunnel LVOTO.Diameter of aortic ring ranges from 12.0 to 16.4 mm,and pressure gradient across the stenotic region ranges from 90-151 mm Hg.8 cases were implanted with St.Jude AG19 while 5 cases implanted with St.Jude AG17.Results All 13 cases survived.The 4th patient was implanted permanent epicardial pacemaker for transient Ⅲ AVB.The 4th and 5th patients were found residual ventricular septal repture at the nadir of ventricular incision,one underwent redo procedure while another is being followed up.All cases take cumadine to sustain INR at 1.8-2.5.No death emerges during follow-up period.The motality is 0％,the incidence rate of B is 7.7％,residual VSD 15.4％ and endocarditis 7.7％.Conclusion Konno-Rastan procedure is a promising techi.to relieve LVOTO.However,this complex procedure may lead to several fetal complications.Success of the surgery demands perfect operations.

Objective:To sum up the experience of surgical repair for infants with absence of right pulmonary artery(ARPA) in our hospital to improve the treatment of ARPA.Methods:From February 2019 to April 2019, 3 infants with ARPA underwent surgical repair in our hospital, aged from 33-day to 20-month. We took enhanced CT scan with three-dimensional reconstruction and pulmonary vein wedge angiography(PVWA) to confirm the diagnosis and to assess the surgical indications. We explored to mobilize the atresia patent ductus arteriosus(PDA) and adopted "two-segment" technique to reconstruct the absent pulmonary artery. The blood flow in the "neo" pulmonary artery, the improvement of the pulmonary hypertension and anticoagulant therapy were followed up closely after the operation.Results:There were particular traces on CT reconstruction images which were very important cues for cardiac surgeons inferring potential approaches during the operation, such as the aberrant "diverticulum" or "bud" in the position of the base of the innominate artery in all 3 infants which were confirmed as one end of the atresia PDA connecting the right pulmonary hilum; PVWA which can clearly show the development and distribution of the pulmonary vessels within the lung was taken in one patient. Significant alleviation of pulmonary hypertension happened immediately after the RPA reconstruction; 3 patients recovered smoothly. During early follow-up, RPA thrombosis happened in one patient was cured by continuous pumping anticoagulation with heparin. Now warfarin or aspirin was used with close follow-up.Conclusion:ARPA is not "no-fly zone" for surgical correction. Earlier diagnosis and pulmonary reconstruction in infant could get excellent early result. Some particular aberrant "diverticulum" on CT reconstruction images are important cues with PVWA still being the golden standard for diagnosis and assessment.

Objective The aim of this study is to retrospectively analyze surgical management of absent pulmonary valve syndrome(APVS).Methods Between January 2005 and January 2012,totally 11 children with APVS underwent primary surgical correction.There were 7 boys and 4 girls.Age at surgeries range from 1 to 5 years,and wcight from 10.2-17.5 kg,with average (12.3 ± 3.4) kg.Surgical procedures include VSD repair,pulmonary arteries reconstruction and RVOT reconstruction with monocusp valve.5 cases chose Lecompte maneuver as an option to release compression to bronchus,5 cases underwent fibroscopy inspection and airway secretion suction,and 4 cases adapted deep hypothermic circulatory arrest (DHCA)during correction procedures.All survivors are routinely followed-up with echocardiogram.Results All 11 cases survived,2 of them suffered from frequent lungs infections during the first year post surgery.No case exists bronchus or pulmonary arteries compression.Conclusion APVS is a rare congenital heart defect,which may challenge perioperative managements and operations.Ideal surgical correctiou includes RVOT reconstruction,decompression of bilateral bronchus,and airway inspection with fibroscopy.However,compression of intrapulmonary bronchi by abnormally branching pulmonary arteries may expose patients to a relative long time of medication therapy after surgical correction.A large number of patients with long-term follow-up are needed to draw definitive conclusions on this strategy' s effectiveness.

Objective To investigate the expression of miRNA-301a-3p in pancreatic cancer and to correlate the expression on invasion , migration and colony formation of pancreatic cancer cells .Methods The expression of miRNA-301a-3p in 20 paired pancreatic cancer tissues and matched adjacent tissues , and pancreatic cancer cell lines and normal pancreatic ductal cells were detected by real -time PCR.miRNA-301a-3p mimics or inhibitors were used to up-regulate or down-regulate the miRNA-301a-3p level in pancre-atic cancer cell lines in order to figure out the effects of miRNA-301a-3p on cell invasion, migration and col-ony formation of pancreatic cancer cells , respectively .Results In pancreatic cancer tissues and cell lines , miRNA-301a-3p was significantly up-regulated when compared with the matched adjacent tissues ( P <0.05) and normal pancreatic ductal cells (P<0.05), respectively.Overexpression or downexpression of miRNA-301a-3p enhanced or suppressed colony formation , invasion and migration abilities of pancreatic cancer cells in vitro.Upregulation of miRNA-301a-3p promoted tumorigenesis in vivo.Conclusion miR-NA-301a-3p might function as an oncogene to promote tumorigenesis in pancreatic cancer .