OBJECTIVETo study the effects of two different endodontic sealers on the bond strength of two fiber posts cemented with adhesive resin cement.

METHODSTwenty-eight crownless human maxillary central incisors were prepared with the step-back technique and randomly divided into four groups according endodontic sealer and fiber: Group A, Cortisomol sealer+Matchpost fiber post; Group B, Cortisomol sealer+Macrolock fiber post; Group C, Guttaflow sealer+Matchpost fiber post; Group D, Guttaflow sealer+Macrolock fiber post. One week after fiber posts were bonded, a thin-slice push-out test was performed in a universal machine. Morphologic structure of the root canal dentin surfaces etched and the adhesive interfaces were examined by scanning electron microscopy (SEM).

RESULTSThe bond strengths of 4 groups were (7.06 +/- 3.22), (9.31 +/- 3.61), (6.90 +/- 3.13), (9.71 +/- 3.42) MPa. The bond strengths of group B and D were significantly higher than that of group A and C (P < 0.05). There was no significant difference between group A and C, group B and D (P > 0.05). The cervical third had the highest mean push-out bond strength, next to middle third and apical third (P < 0.01). SEM showed that larger numbers of the dentin tubules were open after the root canals were etched and penetration of resin tags into the dentinal tubules increased in the coronal root region when compared with the apical root region.

CONCLUSIONThe shear bond strength doesn't have relationship with endodontic sealers. The serration significantly increases the retention of fiber post. The bond strengths are different at the three root segment sites.

Dental Bonding ; Dentin ; Dentin-Bonding Agents ; Dimethylpolysiloxanes ; Drug Combinations ; Gutta-Percha ; Humans ; Incisor ; Post and Core Technique ; Resin Cements ; Root Canal Therapy ; Tooth Root ; Zinc Oxide-Eugenol Cement

Objective To observe the effect of the nutrition management according to the JCI(Joint Commission on Accreditation of Healthcare Organizations)management standard for critically ill pediatric patients with mechanical ventilation.Methods A total of 330 cases with mechanical ventilation were en-rolled in the control group from Hunan Province Children's Hospital PICU between Jan.2012 and Dec.2012, and these pediatric patients were managed with the conventional nutrient management.A total of 359 pediatric patients with mechanical ventilation were admitted to the experimental group from Jan.2013 to Dec.2013 and these patients were managed with nutrient management based on JCI standards.The length of mechanical venti-lation,stay in ICU,stay in hospital were compared between two groups,and the incidence of ventilator-associ-ated pneumonia,abandonment rate and mortality were also compared between experimental group and control group.Results The length of mechanical ventilation in control group[(8.39 ±1.34)days]was longer than that of experimental group[(5.69 ±1.12)days].The length of stay in PICU for control group[(12.32 ± 1.37)days]was more than that in experimental group[(9.42 ±1.53)days].The length of stay in hospital for control group [(15.37 ±2.16 )days]was higher than that of experimental group [(12.63 ±2.29 ) days].The incidence of ventilator-associated pneumonia(9.7%)in control group was higher than that of ex-perimental group,and the giving up or mortality rate in control group(8.48%)was higher than that of exper-imental group(4.35%).And there were significant differences by statistical analysis(P ﹤0.01 ,respective-ly).Conclusion According to the nutritional management in JCI standard,the length of mechanical ventila-tion,stay in PICU and stay in hospital time,the incidence of ventilator-associated pneumonia,and the aban-doned or mortality rate were reduced for critically ill pediatric patients with mechanical ventilation.

Objective To investigate the efficacy and application of bronchoalveolar lavage in chil-dren with severe pneumonia undergoing mechanical ventilation. Methods Using a prospective randomized controlled clinical study, 202 children with severe pneumonia received mechanical ventilation in Hunan Children′s Hospital from January 2016 to January 2018 were selected as the subjects. According to the digital method,all cases were divided into treatment group (101 cases) and control group (101 cases) randomly. The patients in the control group were given conventional treatment ( anti-infection and symptomatic thera-py) . The treatment group was treated with bronchoalveolar lavage on the basis of conventional treatment. The basic situation,the respiratory function before and after the treatment,the inflammation index,the curative effect and the prognosis of two groups were analyzed. Results There were no significant differences between the two groups in gender,age,course pre-admission,pediatric critical illness score,respiratory function and in-flammation index ( P>0. 05 ) . The respiratory function indexes of the treatment group were obviously im-proved 2 hours after the treatment and the PaO2 ,PaO2/FiO2 and SaO2 were significantly higher than those of the control group[PaO2:(82. 4 ± 6. 4) mmHg(1 mmHg=0. 133 kPa) vs. (74. 0 ± 5. 5) mmHg, PaO2/FiO2:(360. 2 ± 21. 3) mmHg vs. (332. 6 ± 23. 5) mmHg,SaO2:(94. 9 ± 8. 2)％ vs. (88. 6 ± 10. 3)％], while the PaCO2 were significantly lower than the control group [ ( 37. 3 ± 10. 3 ) mmHg vs. ( 45. 8 ± 5. 5 ) mmHg],and the differences were statistically significant (P<0. 05). Five days after treatment,the WBC, PCT and CRP of treatment group were significantly lower than those in the control group[WBC:(8. 5 ± 2. 4) × 109/L vs. (11. 7 ± 3. 5) × 109/L,PCT:(1. 2 ± 0. 7) μg/L vs. (2. 3 ± 0. 9) μg/L,CRP:(9. 1 ± 3. 2) mg/L vs. (16. 5 ± 4. 7) mg/L,P<0. 05,respectively]. The total effective rate in the treatment group was significantly higher than that in the control group[93. 1％(94/101)vs. 81. 2％(82/101)]. Mechanical venti-lation duration and PICU stay in treatment group were significantly shorter than those in the control group [(148. 5 ±30. 6)h vs. (159. 6 ±47. 3)h,(220. 8 ±49. 7)h vs. (330. 7 ±94. 6)h]. The positive rate of patho-genic bacteria was significantly higher than that in the control group [79. 2％(80/101)vs. 62. 4％(63/101), P<0. 05],but there was no significant difference in the 28 days mortality of the two groups[5. 0％(5/101) vs. 5. 9％(6/101),P>0. 05]. Conclusion The bronchoalveolar lavage can improve the respiratory func-tion,reduce the inflammatory reaction,shorten mechanical ventilation duration and PICU stay in children with severe pneumonia undergoing mechanical ventilation obviously. It is worth popularizing in the PICU because of the improvement of curative effect in these children.

Objectives To determine the risk factors of ventilator-associated pneumonia (VAP) in the pediatric intensive care unit and to explore effective strategies to reduce the morbidity of VAP. Methods A retrospective analysis was conducted on 455 children admitted into the PICU of Hunan Children's Hospital from June 2014 to June 2017. The 455 children were divided into VAP group (n=43) and non-VAP group (n=412). The incidence of VAP was identified and risk factors were compared using the logistic regression analysis via SPSS 19.0 software.Results There were 311 males and 144 females with a median age of 11 months old (29 days to 9 years and 4 months). The incidence of VAP was 9.45% (43/455). Congenital laryngeal and trachea malformation with pulmonary infection was the first reason for the occurrence of VAP (23.3%), followed by congenital heart diseases with pulmonary infection (18.6%). Via univariate analysis, types of endotracheal intubation (χ2=45.33, P<0.001), duration of mechanical ventilation (Z=1.21, P=0.034), re-intubation (χ2=20.22, P=0.004), early usage of antibiotics (χ2=4.98, P=0.026),and methods of nutritional support(χ2=10.15,P=0.006)were identified as risk factors of VAP in the pediatric intensive care unit patients (P<0.05). Based on the multivariate logistic regression analysis, the followings were all independent predictor for VAP:types of endotracheal intubation(OR=1.87,95%CI:1.48~9.75),duration of mechanical ventilation(OR=1.14, 95%CI:1.08~2.35), re-intubation (OR=3.42, 95%CI:1.26~5.57), early usage of antibiotics (OR=4.55, 95%CI:2.21~8.77). Conclusions Many risk factors were found related with the occurrence of VAP. A comprehensive analysis of the host factors and iatrogenic factors should be conducted. Rational use of antibiotics and daily assessment of extubation might help reduce the incidence of VAP.

Objective:To investigate the efficacy and safety of dexmedetomidine in noninvasive continuous positive airway pressure(NCPAP)for acute respiratory failure in children.Methods:Clinical data of children with acute respiratory failure who underwent NCPAP from January 2018 to March 2020 in PICU of Hunan Children′s Hospital were prospectively collected.They were randomly divided into dexmedetomidine group(group D)and midazolam group(group M), with a total of 100 children.We compared the sedation depth of the two groups at 7 time points after sedation at 0.5 h(t1), 1 h(t2), 2 h(t3), 6 h(t4), 12 h(t5), 24 h(t6), and 48 h(t7), time to reach proper sedation, NCPAP time, NCPAP failure rate, oxygenation index(P/F value)before sedation(T0)and 1h(T1), 24h(T2), and 48h(T3)after sedation, and the main vital signs and adverse reactions before sedation(T0)and 1h(T1), 24h(T2), 48h(T3)after sedation.Results:(1)The proportion of proper sedation at T4, T5, T6 and T7 after sedation in group D was higher than that in group M[98%(49/50)vs.84%(42/50), 94%(47/50)vs.90%(45/50), 96%(48/50)vs.88%(44/50), 90%(45/50)vs.88%(44/50), χ2=6.538, 8.043, 8.174, 7.678, all P<0.05]. Time to reach proper sedation in group D was shorter[(58.6±7.9)s vs.(66.7±9.3)s, t=4.682, P<0.01]. (2)The treatment time and failure rate of NCPAP in group D were lower than those in group M[(134.9±25.5)h vs.(147.8±24.3)h, 10%(5/50)vs.28%(14/50), all P<0.05]. P/F after NCPAP treatment in the two groups was improved as compared with that before treatment(all P<0.01), and the improvement was more significant in group D than in group M at T2 and T3 after sedation[(199.3±26.1)vs.(188.5±24.2)mmHg, (212.2±25.4)mmHg vs.(200.8±24.8)mmHg, t=2.132, 2.278, all P<0.05]. (3)There were no significant differences in heart rate(HR), mean arterial pressure(MAP), and respiratory rate(RR)before sedation between the two groups(all P>0.05). HR and RR after sedation in both groups decreased as compared with those before sedation( P<0.01). HR at T1, T2, and T3 after sedation in group D decreased more significantly than that in group M[(116.3±17.6)bpm vs.(124.8±14.1)bpm, (110.2±18.4)bpm vs.(121.9±15.2)bpm, (108.5±18.7)bpm vs.(117.6±12.8)bpm, t=0.479, -3.474, -2.840, all P<0.05]. There was no significant difference in RR after sedation between the two groups( t=1.872, 1.632, 1.675, all P>0.05). MAP at T1 in group D decreased as compared with T0( P<0.01). MAP at T1 in group D was lower than that in group M[(65.5±5.1)mmHg vs.(68.0±5.7)mmHg, t=-2.297, P=0.024]. (4)There was no significant difference in the incidence of total adverse reactions between the two groups[20%(10/50)vs.14%(7/50), P=0.595]. The incidence of bradycardia was higher in group D than in group M[16%(8/50)vs.2%(1/50), P=0.031]. Conclusion:The incidence of adverse reactions of dexmedetomidine and midazolam in the sedation of NCPAP in children with acute respiratory failure is similar, but the sedative effect of dexmedetomidine is better than that of midazolam in the improvement of pulmonary oxygenation.

Objective:To investigate the efficacy and safety of bronchoscopic lavage in children with severe adenoviral pneumonia.Methods:Patients with severe adenovirus pneumonia who were admitted to ICU department of Hunan Children′s Hospital for bronchoscopy were collected from February to June 2019 and divided into lavage group( n=36) and non-lavage group( n=15) in line with whether lavage was performed.Their results, namely, bronchoscopic diagnosis, blood gas analysis before and 2 hours, 24 hours and 48 hours after bronchoscopy, improvement time of clinical symptoms(fever and pulmonary moist rales), the positive rate of pathogen detection and mortality rate, main vital signs such as heart rate, respiratory rate, mean arterial pressure and bronchoscopy-related complications were recorded before and 1 hour, 2 hours and 24 hours after bronchoscopy. Results:A total of 51 children were collected, all of whom suffered from endobronchitis.More secretions were observed in the airways of 36 patients in the lavage group, and only a little or no secretions were observed in 15 patients in the non-lavage group.P/F value and PCO 2 at 2 hours, 24 hours and 48 hours after treatment in the lavage group were improved comparing to those before treatment and were superior to those in the non-lavage group( P<0.05). P/F values at 24 hours and 48 hours after treatment in the non-lavage group increased and PCO 2 decreased at 48 hours after treatment( P<0.05). The thermal duration, time to resolution of moist rales in the lungs in the lavage group were shorter than those in the non-lavage group( P<0.05). The mortality rate in the lavage group was lower than that in the non-lavage group[2.8%(1/36) vs.26.7%(4/15), P<0.05]. The positive rate of pathogen detection in lavage group was higher than that in non-lavage group[55.6%(20/36) vs. 20.0%(3/15), P<0.05]. There was no significant difference in heart rate, respiratory rate, and mean arterial pressure at each time point before and after bronchoscopic treatment( P>0.05). Associated complications were 11 cases of intraoperative transient hypoxemia, four cases of bronchial mucosal bleeding, and one case each of postoperative hypoxemia, intraoperative hypertension and hypotension.There was no significant difference in the incidence of complications between the two groups( P>0.05). Conclusion:Bronchoscopic lavage, in treating children with severe adenovirus pneumonia, may improve clinical symptoms, respiratory function, and rate of pathogen detection, reduce mortality, and is effective and safe.

Objective To investigate the prevalence of pulmonary fungal infection and drug resist-ance of the pathogenic fungi among children with severe diseases in pediatric intensive care unit(PICU). Methods From July 2013 to June 2017,the complete clinical data,results of fungal culture and drug sensi-tivity of bronchoalveolar lavage fluid in 112 critically ill children with pulmonary fungus infection of PICU hospitalization in our hospital were collected. Samples of peripheral venous blood were collected meantime, including blood routine examination,C reactive protein,G test and GM test. Results One hundred and twen-ty-six fungi were isolated from sputum samples in 112 critically ill children. Severe pulmonary infection (30. 36%,34/112) was the most common form of the primary diseases, the next were severe sepsis (16. 07%,18/112)and severe malnutrition(15. 18%,17/112). Classified based on age difference,the first one was ＜1 year old (43. 75%,49/112),the second one was 1 to 3 years old(29. 46%,33/112). The fun-gal strains were predominantly Candida albicans (61. 90%) and Candida tropicalis (16. 67%),among the infectious cases 14 were diagnosed as mixed infection. Two cases of 3 cryptococcal infectious children were HIV infection,another one was malignant tumor,Cryptococcus was cultured in both sputum,pleural effusion and cerebrospinal fluid. The drug resistance rate of fluconazol in 126 strains of fungi was 12. 70%,the rate of itraconazole was 7. 14%. Generally,the fungi cultured were with very low resistance to 5-fluorocytosine,vori-conazole and amphotericin B. However,the strains of Aspergillus fumigates,Candida kruse,Candida parapsi-losis and Cryptococcus were highly resistant to fluconazol and itraconazole,but with very low resistance to 5-fluorocytosine and amphotericin B. Conclusion Candida albicans is the main pathogenic fungus of pulmo-nary fungal infection among children in PICU,and we could choose voriconazole and amphotericin B as treat-ment of critically ill children with pulmonaty fungal infection.

Objective:To explore the clinical characteristics of children with septic shock and analyze the drug resistance of blood culture positive bacteria.Methods:The clinical data,positive blood culture strains and drug sensitivity results of 127 children with septic shock admitted to the Department of Intensive Care Medicine of Hunan Children's Hospital from September 2015 to August 2021 were retrospectively analyzed.Results:A total of 134 strains of bacteria or fungi were isolated from the blood culture samples of 127 children with septic shock,and gram-negative strains were the main ones,accounting for 67.16% (90/134).Haemophilus influenzae and Escherichia coli were the main gram-negative bacteria,accounting for 38.81% (52/134) and 20.15% (27/134)，respectively,while Streptococcus pneumoniae was the main gram-positive bacteria,accounting for 8.21% (11/134),and Candida albicans was the main fungus,accounting for 10.45% (14/134).The number of white blood cells,the levels of serum C-reactive protein,procalcitonin,venous blood sugar and arterial blood lactic acid in patients were all significantly higher than normal values,and the white blood cells count and neutrophil percentage in gram-positive bacterial infections were significantly higher than those with gram-negative bacterial infections and fungal infections( P<0.05).Procalcitonin increased most obviously when infected by gram-negative bacteria,and the difference was statistically significant ( P<0.05).Gram-positive strains were sensitive to vancomycin,teicoplanin,and linezolid,but only 50% of Streptococcus pneumoniae were sensitive to penicillin.Gram-negative strains had relatively high drug resistance,among which Klebsiella pneumoniae were only highly resistant to imipenem,cilastatin and levofloxacin,reaching 50%.Haemophilus influenzae was resistant to cephalosporins and β-amides enzyme antibiotic,and the drug sensitivity rate of lactamase antibiotics was high,with a resistance rate of 50% only to ampicillin,cefuroxime,amikacin,and compound sulfamethoxazole.There were not many fungal strains,and most antifungal drugs were effective against blood culture-positive fungi. Conclusion:The main pathogens of infection in children with septic shock are gram-negative bacteria,and have high resistance to general antibiotics.We should pay attention to their drug resistance when using antibiotics empirically.

ObjectiveTo observe the effect of combination of partial body weight support and functional electrical stimulation on lower limb motor function for stroke patients. MethodsFrom January, 2023 to February, 2024, 60 stroke patients from Rehabilitation Hospital of Chancheng District People's Hospital in Foshan City were randomly divided into control group (n = 30) and observation group (n = 30). The control group received routine rehabilitation, while the observation group received a combination of celestial orbit system and functional electrical stimulation in addition, for three weeks. They were assessed with Balance assessment and training system, Berg Balance Scale (BBS), Fugl-Meyer Assessment-Lower Extremities (FMA-LE) and Holden Functional Ambulation Category (FAC) before and after treatment. ResultsX-axis trajectory length, average speed of swaying, total wobble trajectory, Y-axis trajectory length, trajectory length per unit area, BBS score, FMA-LE score and FAC score improved in both groups after treatment (|t| > 4.809, P < 0.001); and all the indexes improved more in the observation group than in the control group (|t| > 2.268, P < 0.05), except X-axis trajectory length and average speed of swaying. ConclusionSupplement of the combination of partial body weight support and functional electrical stimulation is more effective on lower limb motor function, balance and walking for stroke patients.