Objective:To compare the accuracy of dynamic navigation system,fully-guided and Pilot-drill guided implant surgery in anterior dental aesthetic area.Methods:45 patients underwent single tooth implantation in anterior dental aesthetic area were random-ly divided into 3 groups(n=15).Dynamic navigation system imlanting(A),3D printing fully-guided template with ASTRA EV assis-ted orthopedic implantation(B)and Pilot-drill guided implantation(C)were respectively used for the patients in group A,B and C.The deviation between the preoperative design and actual results were measured by CBCT and/or 3D reconstruction with navigation de-sign software or 3SHAPE software.SPSS 25.0 software package was used and(x)±s was used for descriptive analysis,results were pair-wise compared among the 3 groups using ANOVA.Results:Data were normally distributed and the variance of the data was homoge-neous.In group A,the distance deviation of implant top center was(0.571±0.196)mm,the horizontal deviation was(0.405±0.222)mm,the distance deviation of implant apical center was(0.449±0.267)mm,the vertical deviation was(0.312±0.223)mm,the de-viation of the connection angle between the two centers was 2.257°±0.989°.In group B,those were(0.520±0.242)mm,(0.219±0.201)mm,(0.643±0.284)mm,(0.464±0.292)mm and 1.272°±0.951° respectively.In group C those were(1.179±0.365)mm,(0.667±0.276)mm,(1.518±0.566)mm,(0.967±0.444)mm and 2.568°±0.632°.The deviation of all the measurments of group A and B was lower than those of group C(P＜0.05).The deviation of the connection angle between the 2 centers of group B was less than that of group A(P＜0.05),but no statistical significance(P＞0.05)was found in other 4 measured items.Conslusion:The accuracy of the dynamic navigation system and the fully-guided implantation is significantly higher than that of the Pilot-drill guided implantation,but is not statistically significant between dynamic navigation and the fully-guided system.

Objective:To summarize the clinical features of 8 cases with intramycardial hematoma(IMH) following congenital cardiac surgery in children.Methods:We retrospectly searched 8 patients with intramycardial hematoma after congenital cardiac surgery in Guangzhou Women and Children’s Medical Center from 2008 to 2024.Results:Mean age and mean weight at surgery were(13±15) months and(7.8±3.5)kg respectively. 6 of 8 cases were interventricular septal hematoma. In the other 2 patients, intramycardial hematoma was located in left ventrical free wall. All IMH were postoperatively detected by transthoracic echocardiaography. Two patients were managed with ECMO intraoperatively. Finally, all patients were discharged successfully with good clinical results. Mean time to IMH resolution in six patients was(33.5±4.6) days and mean left ventricular ejection fraction(LVEF) was 0.60±0.09. Another patient was followed up for 3 months and the IMH was not absorbed. One patient was lost to follow-up.Conclusion:IMH is a rare complication after congenital heart disease. The absorption of hematoma is a dynamic process and mean time to IMH resolution is about 1month. In IMH patients with hemodynamic instability, ECMO can be a good treatment to create opportunities for hematoma absorbtion.

Znic (Zn) alloys with good cytocompatibility and suitable degradation rate have been a kind of biodegradable metal with great potential for clinical applications. This paper summarizes the biological role of degradable Zn alloy as bone implant materials, discusses the mechanical properties of different Zn alloys and their advantages and disadvantages as bone implant materials, and analyzes the influence of different processing strategies (such as alloying and additive manufacturing) on the mechanical properties of Zn alloys. This paper provides systematic design approaches for biodegradable Zn alloys as bone implant materials in terms of the material selection, product processing, structural topology optimization, and assesses their application prospects with a view to better serve the clinic.
Orthopedics ; Zinc ; Alloys ; Dental Materials ; Prostheses and Implants

Objective To compare the correlation and consistency of liquid chromatography-tandem mass spectrometry(LC-MS/MS)and electrochemiluminescence immunoassay(ECLIA)in the determination of se-rum 25-hydroxyvitamin D[25(OH)D],in order to guide the clinical selection of appropriate detection meth-ods.Methods A total of clinical serum samples were collected from the laboratory,and 25(OH)D levels were detected by LC-MS/MS and ECLIA,respectively.Passing-Boblok regression was used to analyze the correla-tion between the two methods,and Bland-Altman and Mountain plot were used to evaluate the agreement be-tween the two methods.Serum 25(OH)D<20.0 ng/mL was defined as vitamin D deficiency,and serum 25(OH)D as 20.0-<30.0 ng/mL was defined as vitamin D insufficiency.Kappa analysis was used to determine the coincidence rate of the two methods in the diagnosis of vitamin D nutritional status.Results The 25(OH)D levels detected by LC-MS/MS and ECLIA were(26.67±4.79)ng/mL and(39.33±4.09)ng/mL,respec-tively.The regression equation of the two methods was YECLIA=-4.558 1+1.719 8XLC-MS/MS,the slope was 1.719 8(95%CI 1.586 3-1.828 4),excluded 1,and the intercept was 4.558 1(95%CI-7.692 2--2.122 1),excluded 0,prompt system difference or ratio differences of the two methods.There were system-atic or proportional differences between the two methods.The Bland-Altman figure showed two methods aver-ages was 12.7,and the difference of out points(ratio)was 3.19%.The peak value of the mountain plot was-9.17 ng/mL,with more deviations from 0,indicating poor agreement between the results measured by the two methods.The Kappa coefficient of the two methods for judging vitamin D deficiency was 0.875,and the diagnostic coincidence rate was 94.68%.The Kappa coefficient of the two methods for judging vitamin D in-sufficiency was 0.538,and the diagnostic coincidence rate was 75.53%.Conclusion The agreement between ECLIA and LC-MS/MS is poor,but the agreement between ECLIA and LC-MS/MS in the diagnosis of vita-min D deficiency and insufficiency based on nutritional status is high.

Objective    To summarize the results of surgical treatment for 79 patients with coarctation of the aorta (CoA) combined with complex anomalies (CA) in recent years. Methods    The data from 79 patients with CoA combined with CA admitted to Guangzhou Women and Children's Medical Center between January 19, 2010 and September 7, 2017 were collected and analyzed. There were 52 males and 27 females. The median age was 71 days, and the median weight was 4.3 kg. There were 26 patients combined with tracheostenosis and 7 patients with preoperative tracheal intubation. Extended end-to-side anastomosis was used to correct the CoA, and the associated cardiac abnormalities were treated simultaneously by an incision through median sternotomy. All operations were performed by the same group of surgeons. Results    The median deep hypothermic circulatory arrest was 18 (13-28) minutes, the median aorta cross-clamp time was 62 (15-199) minutes, the median cardiopulmonary bypass time was 145 (71-674) minutes, the median ventilation time was 72 (9-960) hours, the median length of ICU stay was 144 (12-1 944) hours, and the median length of hospital stay was 24 (2-93) days. Early death occurred in 9 patients and late death occurred in 5 patients. Reoperation occurred in 28 patients and recoarctation developed in 10 patients. After operation, transcoarctation gradient was reduced, and the transcutaneous oxygen saturation, C-reactive protein (CRP), lactate and creatinine were increased. Compared to the survival group, both preoperative and postoperative transcutaneous oxygen saturation were worse and the postoperative levels of plasma brain natriuretic peptide (BNP) and CRP were higher in the death group. Conclusion    Correcting the CoA and the associated CA simultaneously with extended end-to-side anastomosis by an incision through median sternotomy is effective and safe, and the outcomes of immediate and medial-term are satisfactory. Improving oxygenation and limiting elevation of BNP and CRP levels may reduce the death rate.

Objective To evaluate the role of α2A adrenergic receptor (α2AAR) in dexmedetomidine-induced inhibition of TLR4/NF-κB signaling pathway activation during hypoxia-reoxygenation (H/R)caused injury to alveolar type Ⅱ epithelial cells.Methods Type Ⅱ] alveolar epithelial cells of rats RLE6TN cells cultured in vitro were divided into 4 groups (n =6 each) using a random number table method:control group (group C),H/R injury group (group H/R),dexmedetomidine group (group D) and α2A AR small interfering RNA (siRNA) plus dexmedetomidine group (group α2AAR-siRNA+D).H/R was produced by exposing cells to 1％ O2-5％ CO2-94％ N2 for 24 h followed by 4-h reoxygenation.Cells were incubated for 1 h with dexmedetomidine at the final concentration of 1 nmol/L,and then H/R model was established in group D.In group α2AAR-siRNA+D,cells were transfected with 50 nmol/L α2AAR-siRNA,48 h later dexmedetomidine at the final concentration of 1 nmol/L was added,cells were incubated for 1 h,and then H/R model was established.The cell viability was measured using CCK-8 method,cell apoptosis rate was determined by flow cytometry,and the expression of TLR4 and NF-κB was detected by immunofluorescence.Results Compared with group C,the cell viability was significantly decreased,the apoptosis rate was increased,and the expression of TLR4 and NF-κB was up-regulated in group H/R (P＜0.05),and no significant change was found in the parameters mentioned above in group D (P＞0.05).Compared with group H/R,the cell viability was significantly increased,the apoptosis rate was decreased,and the expression of TLR4 and NF-κB was down-regulated in group D (P＜0.05),and no significant change was found in the parameters mentioned above in group α2AAR-siRNA+D (P＞0.05).Compared with group D,the cell viability was significantly decreased,the apoptosis rate was increased,and the expression of TLR4 and NF-κB was up-regulated in group α2AAR-siRNA+D (P＜0.05).Conclusion The mechanism by which dexmedetomidine inhibits TLR4/NF-κB signaling pathway activation may be related to activating α2AAR during H/R-caused injury to alveolar type Ⅱ epithelial cells.

Objective To assess the application value of juxtaposition of the great vessels in diagnosis of right atrial isom-erism( RAI) by echocardiography.Methods We retrospectively analyzed 73 patients with right atrial isomerism in Guangzhou Women and Children's Medical Center from 2010-2017.All these patients were performed by echocardiography and compu-ted tomography(CT).We used the results of CT as the golden standard.Results 73 cases of RAI were diagnosed by CT.60 cases of RAI were diagnosed by echocardiography.Juxtaposition of the descending aorta(DAO) and inferior vena(IVC) was demonstrated in all these 60 patients.29 of 60 were on the left side of the spine(39.73％).31 of 60 were on the right side of spine(42.47％).In the other 13 patients of echocardiography missed diagnosis, the arrangement of the great vessels was nor-mal in 10 cases, and inverse in 3 cases.Conclusion Juxtaposition of the great vessels is one of the most important findings in patients with RAI.It is quick and simple and has a higher application value in diagnosis of RAI.

Objective To summarize the outcomes and experience of arterial switch operation (ASO) in the past 10 years in our center.Methods From September 2008 to July 2017,238 patients underwent ASO at Guangzhou Women and Children Medical Center for repair of transposition of the great arteries and Taussig-Bing anomaly.There were 193 male and 45 female.Median age at operation was 2 months (2 days to 10 years) and mean body weight was(4.2 ± 1.7) kg (1.8-20.6 kg).There were TGA and VSD 91 cases,TGA/IVS 110 cases,and Taussig-Bing anomaly 37 cases.Among them 24 patients had an aortic arch anomaly.Intramural coronary artery was found in 8 patients.Results All patients successfully completed the operation,one-stage ASO was perfonned in 232 patients.Two-stage ASO was performed in 6 patients.The mortality was 14.2％.The follow-up duration was 1-10 years (median time,46 mouths).There were 3 died.Two suffered sudden death,and another one arrhythmia.10-year survival rate was 92.8％.Conclusion The outcomes of ASO were satisfactory.The long-term reoperation rate was rare.

Objective To summarize the revascularization surgery results of patients with unilateral absence of a pulmonary artery.Methods From November 2014 to July 2016,5 patients with unilateral absence of a pulmonary artery underwent surgical revascularization at Guangzhou Women and Children Medical Center.The age and body weight at surgery was 1-6 months and 3.9-5.8 kg.One patient was diagnosed with unilateral absence of left pulmonary artery.The other 4 patients were diagnosed with unilateral absence of right pulmonary artery.Three patients were diagnosed with isolated unilateral absence of a pulmonary artery.One was associated with Tetralogy of Fallot.One was associated with atrial septal defect.Revascularization was performed by connection of hilar artery and the main pulmonary artery,using direct anastomosis,Gore-Tex conduit or pericardial conduit.Results There was no mortality.The ICU stay after operation were 3-14 days.The follow-up duration was 14-34 months.All patients were alive and free from significant pulmonary stenosis.Conclusion Revascularization surgery for patients with unilateral absence of a pulmonary artery is effective and achieved satisfactory results.

Objective To further investigate direct effects of dipeptidyl peptidase-4(DPP4) on calcification and to identify responsible signaling pathways in human vascular smooth muscle cells (HVSMC). Methods The effect of DPP-4 on calcification of HVSMC was observed by alizarin red, and Western blot was used to detect whether DPP4 induced calcification-related protein expressions through extracellular signal-regulated kinases 1/2 (ERK1/2) pathway. Results The Alizarin red staining results showed that calcified nodules in DPP4 group were significantly increased as compared with control group, similar to calcification group.The protein expressions of osteoprotegerin (OPG), osteopontin (OPN), Runt-related transcription factor 2 (RUNX2), and bone morphogenetic protein 2 (BMP2) were stimulated by DPP4 in a concentration- and time-dependent manner. The phosphorylation level of ERK1/2 was significantly increased after DPP4 incubation for 15 min (P<0.05). PD98059, an ERK1/2 inhibitor, significantly lowered DPP4-stimulated expressions of calcification-related proteins (P<0.05). Conclusion DPP4 may promote the calcification of HVSMC through ERK1/2 signaling pathways.