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81.
Possible hazardous effects of hydrofluoric acid and recommendations for treatment approach: a review
Hydrofluoric acid (HF) is commonly used for conditioning the glass ceramics either prior to cementation or for intraoral repair
in prosthetic and restorative dentistry. The present study offers a review of chemical properties of HF used, highlight the
possible hazardous effects of this agent, and to recommend the treatment approach for potential risks. Available published
information documented in PubMed, Medline, and Picarta literature databases was reviewed. Additional information was derived
from scientific reports, medical and chemical textbooks, handbooks, product information, manufacturers’ instructions, Internet
web sites of the HF manufacturers. No report was found on the incidence of the hazardous effects of HF in dentistry. Reports
from other fields presented incidences of acute and chronic symptoms in exposure to HF. While acute symptoms include skin
or nail burns, chronic ones involve systemic toxicity, eye injuries, inhalation and ingestion-related symptoms that can be
even fatal. HF can be harmful and particularly aggressive to soft tissues, but symptoms may not be apparent immediately after
exposure. The hazardous effects are not based on the pH value, but on the toxicity of HF. Potential hazards of HF known from
other applications than dentistry should be considered also in dental applications. Especially the clinicians, who often deal
with adhesive cementation or repair of glass ceramics, should take necessary precautions for possible hazards of HF. 相似文献
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84.
G. Gürleyik E. Gürleyik A. Yilmazcan A. Özcan I. Onaran S. Ünalmiser 《Acta chirurgica Belgica》2013,113(1):33-36
The leakage of colonic anastomoses increases perioperative morbidity significantly. The purpose of the study was to investigate the influence of neurotensin, an intestinal trophic peptide, on the healing of colonic anastomosis. Forty-two Wistar-albino rats were separated into three equal groups: Group 1 (control group) — segmental resection of the left colon and end-to-end anastomosis; Group 2 (dexamethasone group) — resection and anastomosis, plus 0.1 mg/kg/day of dexamethasone; Group 3 (neurotensin group) — same surgical procedure plus 300 pg/kg/day of neurotensin. Bursting pressure and tissue hydroxyproline content were determined as parameters of the anastomosis strength and healing on the 3rd and 7th days postoperatively. On the 3rd day, mean bursting pressures were 141.4, 146.7 and 73.1 (p = 0.0001) cm of water in the control group, dexamethasone and neurotensin groups respectively. On the 7th day, bursting pressures were measured as 237.4, 100.6 (p = 0.0001) and 72.7(p = 10-6) cm of water, in the control group, dexamethasone and neurotensin groups respectively. Between the 3rd and 7th days, bursting pressures were increased significantly in the control group (p = 0.0001), decreased in the dexamethasone (p = 0.048), and maintained their lowest values in the neurotensin (p = 0.96) groups. On the 7th day, mean hydroxyproline levels were measured as 9.20, 3.30 (p = 0.007), 2.86 (p = 0.007) pg, in the control group, dexamethasone, and neurotensin groups respectively. Between the 3rd and 7th days, tissue hydroxyproline levels were increased significantly in the control group (p = 0.004), decreased in the dexamethasone (p = 0.03), and maintained their lowest values in the neurotensin (p = 0.87) groups. The anastomosis resistance to intraluminal pressure was weak, tissue collagen content was insufficient, and healing was inadequate in the dexamethasone and neurotensin groups in respect to the control group. We concluded that neurotensin impaired the healing, and affected the strength of the colonic anastomosis. 相似文献
85.
Ercan Erdogan Mehmet Akkaya Ahmet Bacaksiz Abdurrrahman Tasal Osman S?nmez Mehmet Ali Elbey Seref Kul Mehmet Akif Vatankulu Murat Turfan ?mer G?ktekin 《Clinics (S?o Paulo, Brazil)》2013,68(10):1333-1337
OBJECTIVE:
Successful revascularization of chronic total occlusions has been associated with improved left ventricular systolic function, reduced anginal symptoms, increased exercise capacity, and increased survival. This study was conducted to determine the impact of revascularization in chronic total occlusion on left ventricular function using novel echocardiographic techniques.METHODS:
A total of 129 patients with chronic total occlusion who underwent revascularization between April 2011 and November 2012 were included in this study. Echocardiographic assessments with two-dimensional speckle tracking echocardiography and real-time three-dimensional echocardiography were performed before the procedure and one month after the procedure. The left ventricular ejection fraction, left ventricular volumes, and three-dimensional systolic dyssynchrony index were quantified.RESULTS:
An immediate procedural success was obtained in 118 patients (91.5%). There were no acute or subacute stent thromboses during follow-up. The mean left ventricular ejection fraction significantly increased (p<0.001), while the left ventricular end-diastolic and end-systolic volumes significantly decreased (p = 0.001 and p<0.001, respectively). The three-dimensional systolic dyssynchrony index also decreased significantly (p<0.001). The global longitudinal strain showed a significant increase after successful revascularization (p<0.001). An increase in the global longitudinal strain was correlated with an increase in the left ventricular ejection fraction (r = 0.27, p = 0.02). The patients with a left ventricular ejection fraction ≥50% displayed a greater improvement in the global longitudinal strain, and the patients with diabetes showed less improvement.CONCLUSIONS:
Using novel echocardiographic techniques, our results showed that restoring the coronary blood flow in chronic total occlusion patients reduces the left ventricular volumes and improves the left ventricular ejection fraction and the global longitudinal strain of hibernating myocardium. 相似文献86.
Ahmet Bacaksiz Mehmet Akif Vatankulu Mehmet Kayrak Hasan Huseyin Telli Selim S. Ayhan Osman Sonmez Ayse Alp Sadik Buyukbas 《Clinics (S?o Paulo, Brazil)》2013,68(7):997-1003
OBJECTIVES:
Acute ST-elevation myocardial infarction is associated with ventricular dysfunction due to ischemia-induced progressive myocardial damage. The decrease in ventricular compliance causes left atrial dilatation and stretching of the atrial myocardium, which are the main stimuli for the secretion of atrial natriuretic peptide. The aim of this study was to evaluate left atrial dimensions and atrial natriuretic peptide levels in patients early after their first acute ST-elevation myocardial infarction and assess the probable interaction between coronary lesions and these measurements.METHODS:
A total of 110 patients with acute myocardial infarction and 50 controls were studied. Plasma atrial natriuretic peptide was measured at admission. Left ventricular function, diameter, and volume index were evaluated using transthoracic echocardiography. Gensini and vessel scores of the patients who underwent coronary angiography were calculated.RESULTS:
Plasma atrial natriuretic peptide in the patients with myocardial infarction was increased compared with that in controls (3.90±3.75 vs. 1.35±0.72 nmol/L, p<0.001). Although the left atrial diameter was comparable in patients and controls, the left atrial volume index was increased in patients with acute myocardial infarction (26.5±7.1 vs. 21.3±4.9 mL/m2, p<0.01). Multivariate regression analysis showed a strong independent correlation between the left atrial volume index and the plasma atrial natriuretic peptide level (β = 0.23, p = 0.03).CONCLUSIONS:
The left atrial volume index and plasma atrial natriuretic peptide level were correlated in patients with acute myocardial infarction. 相似文献87.
Erhan Çömlekoğlu Erinç Önem Mine Dündar Çömlekoğlu B. Güniz Baksı Ali Mert 《Clinical oral investigations》2013,17(6):1507-1514
Objective
The objective of this study is to compare the diagnostic accuracy of visual inspection (VI) and storage phosphor plate (SPP) radiography for the detection of artificial demineralization bordering different laminate veneers.Materials and methods
Twenty human maxillary canine teeth were prepared. All-ceramic (A) and hybrid ceramic (H) laminate veneers were fabricated and luted. Veneered teeth were covered except for a circular window on the proximal surface bordering restorations. Teeth were kept in acetic acid buffer to create demineralization and imaged with a SPP system. Ten observers evaluated all teeth first visually then with SPP images for the presence/absence of demineralization. Teeth were examined using scanning electron microscopy (SEM) as well. The accuracy was expressed as the area under the ROC curves (A z). Pair-wise comparisons were performed using two-way ANOVA and post hoc t test (p?=?0.05). Fleiss kappa (κ) was used for agreement.Results
SPP radiography was better than the VI for both veneers (p?=?0.004). The A zs of two veneers were different for both VI (p?<?0.005) and SPP (p?<?0.005). SEM evaluation revealed lesions confined to enamel. κ was fair for H, and fair to moderate for A. Agreement was higher for the radiographic evaluation for both veneers.Conclusion
Enamel demineralizations bordering hybrid and ceramic laminate veneers can be detected better with SPP radiography than VI and detectability was better for all-ceramic veneers than the hybrid ceramic ones.Clinical relevance
Early detection of enamel demineralizations bordering laminate veneers would result in time-saving and less-invasive treatment methods; therefore, SPP radiography may be recommended in clinically suspicious cases since it provides better diagnostic accuracy.88.
Binali Çakur DDS PhD Muhammed Akif Sümbüllü DDS PhD Doğan Durna DDS 《Clinical implant dentistry and related research》2013,15(1):83-87
Background: Osseo‐integrated implants are increasingly being used to restore functional dentition; however, in the posterior region, implant placement can be problematic because of inadequate bone height. In this condition, maxillary sinus floor elevation surgery has become the treatment of choice. The presence of anatomic variations within the maxillary sinus such as Underwood's septa and thin schneiderian membrane decreases the success of the sinus floor elevation. Purpose: In this study, we tried to determine the relationship between the anatomic variations of the maxillary sinus: Underwood's septa, schneiderian membrane thickness, and the cortical thickness of the inferior border of the maxillary sinus. Material and Methods: The left and right maxillary sinus images of 74 patients were obtained by using dental computed tomography (CT). The schneiderian membrane and the cortical thickness of the inferior border of the maxillary sinus were measured on the coronal images of dental CT scans at the deepest portion of the sinus cavity. The presence of Underwood's septa was identified on the axial images. The correlations between these variables were assessed. Results: We found that there was only a negative correlation between the schneiderian membrane thickness and the presence of Underwood's septa (r = –0.168 p = .042). Conclusion: It is suggested that Underwood's septa may be the reason for the thinness of the schneiderian membrane. However, future studies among larger groups are necessary for confirming the finding by using well‐designed clinical studies. 相似文献
89.
The aim of this clinical trial was to evaluate the pulsatile perfusion mode in pediatric patients who had complex cardiac pathologies according to Jenkins stratifications (category 4) undergoing cardiopulmonary bypass procedures (CPB). Patients with transposition of great arteries (TGA) and ventricular septal defect (VSD) were included in this clinical study. Eighty‐nine consecutive pediatric patients undergoing open heart surgery for repair of TGA‐VSD were prospectively entered into the study and were randomly assigned to either the pulsatile perfusion group (Group P, n = 58) or the nonpulsatile perfusion group (Group NP, n = 31). There were no differences between groups in terms of demographical and intraoperative parameters. The pulsatile group needed significantly less inotropic support (P < 0.05) and had lower lactate levels (P < 0.001), higher urine output (P < 0.01), and higher albumin levels (P < 0.05). In addition, the pulsatile group had less ICU (P < 0.01) and hospital stays (P < 0.001). We conclude that the use of pulsatile flow is a better option and should be considered for repair of the complex congenital heart defects. 相似文献
90.
Until recently, risk scoring systems for adult patients consisted of only clinical criteria. Currently, we are experiencing an abundant surge of literature integrating a wide range of biomarker arrays to clinical criteria in assessing the risk in an adult. In fact, novel risk scoring systems such as Reynolds criteria have emerged by combining the validated biomarkers to the traditional risk factors. Novel biomarkers potentially improve clinical management of cardiovascular disease, but there are gaps in understanding their role during childhood. The reason might be related to relatively lower prevalence of cardiovascular disease in children compared to the adult population. One exceptional group is the children with congenital heart disease. Recent studies indicate that novel biomarkers can alert the clinician in a timely manner about neurological and myocardial injury and their inflammatory consequences. Current technologies enable us to measure several biomarkers using only a few microliters of plasma. The preliminary studies show that novel biomarkers in addition to the traditionally studied biomarkers can help the clinician to identify children at high risk following pediatric heart surgery. Future studies are needed to confirm the role of biomarkers in monitoring children after cardiopulmonary bypass. 相似文献