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51.
IntroductionThe aim of this in vitro study was to assess and compare the effect of photoactivated disinfection (PAD) on the bond strength of root canal sealers to human root canal dentin using the push-out test.MethodsFifteen extracted human mandibular premolar teeth with single and straight roots were used. After the clinical crowns were removed from the cementoenamel junction, root canals were prepared with the ProTaper (Dentsply Maillefer, Ballaigues, Switzerland) rotary system to the size of the F3 file. The smear layer of the roots was removed using 17% EDTA followed by 5.25% sodium hypochlorite (NaOCl) and distillate water. The roots were then randomly divided into 3 groups (n = 5) according to the final irrigation regimen. In group 1, PAD (FotoSan; CMS Dental, Copenhagen, Denmark) was applied to the root canals and light cured for 20 seconds. Group 2 was finally irrigated with a 2% solution of chlorhexidine gluconate, and group 3 served as the control group (NaOCl + EDTA). All the canals were then obturated with the lateral condensation technique using gutta-percha and AH Plus sealer (Dentsply Maillefer) sealer. One-millimeter-thick horizontal sections from the coronal and midthirds of each root (n: 5 × 4 = 20) were sliced for the push-out bond strength measurement. The data were converted to megapascals and statistically analyzed using 1-way analysis of variance and the post hoc Tukey test.ResultsThere was no significant difference among the bond strength of PAD, chlorhexidine gluconate, and NaOCl (P > .05).ConclusionsWe conclude that PAD does not adversely affect the bond strength of the AH Plus sealer to root canal dentin and that it can be used for the final disinfection of root canals.  相似文献   
52.
Objective:To evaluate the effects of different bleaching methods on the shear bond strength (SBS) of orthodontic brackets.Materials and Methods:Forty-five freshly extracted premolars were randomly divided into three groups (n  =  15 per group). In group I, bleaching was performed with the office bleaching method. In group II, bleaching was performed with the home bleaching method. Group III served as the control. Orthodontic brackets were bonded with a light cure composite resin and cured with an LED light. After bonding, the SBS of the brackets were tested with a Universal testing machine.Results:Analysis of variance indicated a significant difference between groups (P < .001). The highest values for SBS were measured in group III (20.99 ± 2.32 MPa). The SBS was significantly lower in groups I and II than in group III (P < .001). The lowest values for SBS were measured in group II (6.42 ± 0.81 MPa). SBS was significantly higher in group I than in group II (P < .001).Conclusions:Both of the bleaching methods significantly affected the SBS of orthodontic brackets on human enamel. Bleaching with the home bleaching method affected SBS more adversely than did bleaching with the office bleaching method.  相似文献   
53.
AimThis study aimed to compare the fracture resistance of roots filled with a bonded material, fiber posts, or titanium post systems.MethodsCanals in the first group were filled with AH Plus and gutta-percha cones, and roots in the second group were filled with Epiphany sealer and Resilon cones. The root fillings (60 roots) were removed up to 4 mm from the canal apex to obtain 10-mm-deep post spaces, and posts were cemented. The groups were as follows: AH Plus control group, Epiphany control group, AH Plus fiber post group, AH Plus titanium post group, Epiphany fiber post group, and Epiphany titanium post group. Fracture tests were performed by using an Instron testing machine. The force was applied at a 45° axial angle with a constant speed of 1 mm/min. For each sample, the force at which fracture occurred was recorded in units of newtons. Statistical analysis was carried out by using analysis of variance test.ResultsThere was no statistically significant difference between all groups (P > .05).ConclusionsTitanium posts, fiber posts, and Epiphany root canal filling systems were found to have no reinforcing effect on endodontically treated roots.  相似文献   
54.
55.
Background: A tombstoning pattern (T‐pattern) is associated with in‐hospital poor outcomes patients with ST‐segment elevation myocardial infarction (STEMI), but no data are available for midterm follow‐up. We sought to determine the prognostic value of a T‐pattern on admission electrocardiography (ECG) for in‐hospital and midterm mortality in patients with anterior wall STEMI treated with primary percutaneous coronary intervention (PCI). Methods: After exclusion, 169 consecutive patients with anterior wall STEMI (mean age: 55 ± 12.9 years; 145 men) undergoing primary PCI were prospectively enrolled in this study. Patients were classified as a T‐pattern (n = 32) or non–T‐pattern (n = 137) based upon the admission ECG. Follow‐up to 6 months was performed. Results: In‐hospital mortality tended to be higher in the T‐pattern group compared with non–T‐pattern group (9.3% vs 2.1% respectively, P = 0.05). All‐cause mortality was higher in the T‐pattern group than non–T‐pattern group for 6 month (P = 0.004). After adjusting the baseline characteristics, the T‐pattern remained an independent predictor of 6‐month all‐cause mortality (odds ratio: 5.18; 95% confidence interval: 1.25–21.47, P = 0.02). Conclusion: A T‐pattern is a strong independent predictor of 6‐month all‐cause mortality in anterior STEMI treated with primary PCI. Therefore, it may be an indicator of high risk among patients with anterior wall STEMI.  相似文献   
56.
Purpose

Iris claw intraocular lenses (IOLs) were successfully used for the management of aphakia in patients that lack capsular support. The aim of this study was to compare the clinical outcome of prepupillary and retropupillary implantation of these IOLs.

Methods

The files of the 26 patients that had an iris claw IOL implantation between 2010 and 2020 were retrospectively reviewed. Detailed ophthalmological examination findings including corrected distance visual acuity (CDVA), intraocular pressure, endothelial cell counts, slit lamp and dilated fundus examination findings were specifically tabulated. Intraoperative and postoperative complications were also specifically recorded.

Results

There were 18 patients in the prepupillary implantation group and eight patients in the retropupillary implantation group. Age and gender distribution were similar between the groups. CDVA significantly increased in prepupillary and retropupillary implantation groups (p?=?0.001 and p?=?0.012, respectively). Median endothelial cell loss was 6.7% in prepupillary group and 7.2% in retropupillary group. The only intraoperative complication was iridodialysis (n?=?1). Postoperative complications included retinal detachment (n?=?1), cystoid macular edema (n?=?2) and IOL tilt (n?=?1). All of these complications occurred in the prepupillary implantation group.

Conclusion

Prepupillary and retropupillary implantation of iris claw IOLs resulted with similar visual gain and endothelial loss rates in a follow-up time of 6 months. There was an insignificant trend toward a reduced complication rate following retropupillary implantation.

  相似文献   
57.

Purpose

In previous studies, a lack of antibiotic prophylaxis, smoking and obesity were described as factors that contribute to the development of a surgical site infection (SSI) after pilonidal disease (PD) surgery. In this study, we evaluated whether the volume of the excised specimen (VS) was a risk factor for SSI.

Methods

The patients who underwent surgical treatment for PD from January 2010 through December 2011 were retrospectively evaluated in terms of SSI, time off work and healing time. The single and multiple explanatory variable(s) logistic regression analyses were performed.

Results

One-hundred and sixty patients were included in the study. SSI occurred in 19 (11.9 %) patients. In the multiple explanatory variable logistic regression analysis, VS was emerged as a risk factor for SSI (OR 18.78, 95 % CI 2.38–148.10; P < 0.005). The healing time and time off work were longer when a SSI occurred (P < 0.001).

Conclusions

This study suggests that the rate of SSI after the surgical treatment of PD is higher in patients with a high VS. A SSI significantly prolongs the healing time. Surgeons can use this data for assessing the SSI risk. As a preventive measure, prolonged use of an empiric broad-spectrum antibiotic may be beneficial in patients with a high VS.  相似文献   
58.
Background. Increased cardiovascular disease risk is very well known in nephrotic syndrome. Coronary flow reserve measurement by trans-thoracic echocardiography reflects coronary microvascular and endothelial function. However, diastolic filling abnormalities by echocardiography may indicate diastolic dysfunction. Our aim was to evaluate endothelial and diastolic functions by trans-thoracic echocardiography in nephrotic syndrome. Methods. Eighteen patients with nephrotic syndrome (five females, 34 ± 17 years) and 30 controls (10 females, 35 ± 10 years) were evaluated in this cross-sectional observational study. Age, weight, lipid profile, glucose, blood urea nitrogen, creatinine, serum albumin, total protein, C-reactive protein, erythrocyte sedimentation rate, blood pressures, 24-hour urine volume, and protein were recorded. Glomerular filtration rate was estimated by Cockcroft-Gault Formula. Doppler flow and other echocardiographic parameters were measured by Vivid 7 echocardiography. Results. Coronary flow reserve was significantly lower in patients than controls (p < 0.001) and was negatively correlated with proteinuria (p < 0. 001), creatinine levels (p?=?0.03), total cholesterol (p?=?0.02), C-reactive protein (p?=?0.02), and erythrocyte sedimentation rate (p?=?0.005). E/A ratio was significantly lower in patients than in controls (p?=?0.005). DT was significantly higher in patients than in controls (p?=?0.01) and isovolumic relaxation time was similar in both groups. Conclusion. Coronary flow reserve and left ventricular diastolic filling are significantly impaired in nephrotic syndrome. Proteinuria, serum creatinine, total cholesterol and inflammation may have all contributory effects on endothelial dysfunction. Early evaluation of patients with nephrotic syndrome should include coronary flow and diastolic function by echocardiography.  相似文献   
59.
Background. Sudden death is common in end-stage renal disease (ESRD). Cardiac arrhythmia is observed frequently in patients with ESRD and is thought to be responsible for this high rate of sudden death. This study investigated the prevalence and the predictors of arrhythmia in patients on maintenance dialysis. Methods. Ninety-four patients on hemodialysis program were enrolled in the study. Routine laboratory results were noted. Arrhythmia, periods of silent ischemia, and heart-rate variability analyses were obtained from 24-hour Holter monitor recordings. Corrected QT (QTc) dispersion was calculated from 12-lead surface EKG. Echocardiographic and tissue Doppler examinations were performed on interdialytic days as well. Ventricular arrhythmia was classified according to Lown classification; classes 3 and above were accepted as complex ventricular arrhythmia (CVA). Results. The mean age was 52.5±13.2 years; 44 (46.8%) were women. Ventricular premature contractions were detected in 80 (85.1%) patients, of whom 35 (37.2%) were classified as complex ventricular arrhythmia (CVA). Coronary artery disease, hypertension, and QTc dispersion appeared as independent factors predictive of CVA development. Atrial premature contractions (APC) were detected in 53 patients (56.4%) and supraventricular arrhythmia in 15 (16%) patients; all were identified as atrial fibrillation. Duration of dialysis therapy was found as an independent predictor of APC. Conclusion. Arrhythmia is frequently observed in ESRD patients receiving hemodialysis and may be responsible for the high rate of sudden mortality. Hypertension, CAD, and QTc dispersion are independent predictors of CVA, and duration of dialysis therapy is an independent factor affecting APC development in these patients.  相似文献   
60.
The aim of this study is to investigate the healing effect of hyperbaric oxygen (HBO) on colonic anastomoses in the presence of experimentally induced peritonitis. Thirty-two rats were allocated randomly into short-term anastomosis (STA), short-term anastomosis + HBO treatment (STA+HBO), long-term anastomosis (LTA), and long-term anastomosis + HBO (LTA+HBO) treatment groups. The STA and LTA groups were administered fluid resuscitation and antibiotics for 3 and 7 days, respectively, whereas the HBO treatment groups received additional HBO therapy for 3 and 7 days, respectively. The rats were reoperated on the third and the seventh days of anostomoses for evaluation. The bursting pressures in STA+HBO and LTA+HBO therapy groups were significantly higher than those in groups with anastomoses alone (p <. 001 and p <. 01). HBO therapy did not affect the fibrotic index neither in STA nor in LTA groups (p >. 05 for both); however, it was significantly higher in LTA+HBO group than that in STA+HBO group (p <. 05). The hydroxyproline level was significantly higher in LTA group than in STA group (p <. 05), yet HBO therapy did not affect the hydroxyproline levels in STA or LTA groups (p >. 05 for both). It is concluded that hyperbaric oxygen treatment has positive effects on colonic anastomotic healing in case of peritonitis.  相似文献   
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