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51.
52.

Introduction

The aim of the present study was to evaluate crack formation after flaring root canals with Gates Glidden drills and ProTaper Universal (SX; Dentsply Maillefer, Ballaigues, Switzerland), Endoflare (MicroMega, Besançon, France), Revo-S (MicroMega), and HyFlex (Coltene-Whaledent, Allstetten, Switzerland) flaring instruments.

Methods

One-hundred eight mandibular molars were selected. Eighteen teeth were left unprepared to serve as negative controls; the experimental groups consisted of the mesiobuccal and mesiolingual root canals of the remaining 90 teeth, which were instrumented with the following coronal flaring instruments: Gates Glidden drills and ProTaper Universal SX, Endoflare, Revo-S SC1, and HyFlex 25.08 instruments. All roots were then sectioned perpendicular to the long axis at 1, 2, 3, 4, 6, and 8 mm from the cementoenamel junction. The sections were inspected under a stereomicroscope, and any crack formations were recorded. The data were analyzed using the chi-square test (P = .05).

Results

The Gates Glidden drills resulted in a higher rate of crack formation than that noted in the control group (P < .05). Flaring of the root canals using the ProTaper Universal, Endoflare, Revo-S, and HyFlex instruments resulted in crack formation similar to that of the control group (P > .05).

Conclusions

The use of the Gates Glidden drills resulted in the formation of the most cracks. However, the results for the ProTaper Universal, Endoflare, Revo-S, and HyFlex flaring instruments were similar to those of the control group in terms of crack formation.  相似文献   
53.
The purpose of the present study was to assess the effect of solvents on root canal transportation in endodontic retreatment. Sixty extracted human permanent mandibular first molars with curved root canals were selected. All of the root canals were prepared using Twisted File Adaptive instruments (SybronEndo, Orange, CA, USA) and filled with gutta‐percha and AH Plus sealer (Dentsply DeTrey, Konstanz, Germany) using the cold lateral compaction technique. The teeth were assigned to four retreatment groups as follows (n = 15): eucalyptol, chloroform, orange oil and control. The canals were scanned using cone‐beam computed tomography scanning before and after instrumentation. The chloroform group showed a significantly higher mean transportation value than the orange oil and control groups at the 3 and 5 mm levels (P = 0.011 and P = 0.003, respectively). There was no significant difference among the orange oil, eucalyptol and control groups in terms of canal transportation (P > 0.61). The chloroform led to more canal transportation than the eucalyptol and orange oil during endodontic retreatment.  相似文献   
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56.
In this study, we aimed to evaluate the diagnostic accuracy of transthoracic fine needle aspiration (TFNA) specimens in establishing the specific cell type in primary lung cancer and to study the influence of several factors on this accuracy. Forty-six patients with lung cancer diagnosed by TFNA specimens who subsequently underwent thoracotomy between April 2003 and December 2005 were included. Fourty-one patients were men and five were women with a mean age of 59.8 +/- 10 years (34-68 years). TFNA was performed by 22-Gauge Chiba needle with computed tomography guided in all patients. There was cell agreement in 38 of 46 cases (82.6%, Kappa= 0.73). The concordance was 70.8% (Kappa= 0.65) in cases with squamous cell carcinoma and 100% (Kappa= 0.74) in cases with adenocarcinoma (p= 0.01). Stage of the tumor, the diameter and location of the lesion had no effect on cell type agreement (p> 0.05). The concordance was 63.6% in poor differentiated tumors and 92.9% in well differentiated tumors (p> 0.05). Our results pointed out that tumor cell type was the only factor effecting tumor cell type agreement between TFNA and thoracotomy.  相似文献   
57.

Background

Isolated distal vaginal agenesis is a rare anomaly and mostly becomes symptomatic after menarche. We describe an unusual presentation of this anomaly in a prepubertal girl.

Case

An 11-year-old prepubertal girl presented with recurrent urinary tract infection, pyuria, and right-sided renal agenesis. The findings of perineal inspection, ultrasonography, and magnetic resonance imaging were consistent with a distal vaginal agenesis with pyometrocolpos. Discharging pyometrocolpos with dissection of the atretic portion and a pull-through vaginoplasty were performed. A cystoscopy showed no sign of a vesicovaginal or uterine fistula.

Summary and Conclusion

This rare presentation of distal vaginal agenesis reminds us that congenital malformations of the female genital tract should be considered in patients with congenital anomalies of the urinary system and/or recurrent urinary tract infection, even during the prepubertal period.  相似文献   
58.
Objectives: The purpose of this study was to compare the efficacy and safety of two different catheterization techniques of exchange transfusion (ET) used in the therapy of newborn jaundice: fully automated two-way ET technique and the classical one-way ET.

Patients and methods: The study included babies at gestational age of >34 weeks. In total, 107 ETs were performed on 86 babies. Totally, the umbilical vein (UV) group included 54 babies having undergone 69 ETs and the UV/UA group included 32 babies having undergone 38 ETs.

Results: The declines in bilirubin levels right after ET (p?=?0.018) and 8?h after ET (p?=?0.014) were higher in the fully automated UV/UA technique than in the classical UV technique. Furthermore, the duration of intensive phototherapy following ET was shorter in the UV/UA method than in the UV method (p?=?0.003). There was no difference between the two methods in terms of ET-associated complications (p?=?0.927).

Conclusions: In neonatal hyperbilirubinemia, ET with fully automated UV/UA technique is more efficient than the classical ET technique, causing no additional side-effects. It is also more physiological than the classical technique, since it minimizes the fluctuations in the blood volume and intravascular pressure during ET.  相似文献   
59.
We report an elderly patient who developed severe delirium and extrapyramidal signs after initiation of lithium-olanzapine combination. On hospital admission, serum levels of lithium were found to be 3.0 mM/L which were far above toxic level. Immediate discontinuation of both drugs resulted in complete resolution of most of the symptoms except for perioral dyskinesia which persisted for three more months. We critically discussed the differential diagnosis of lithium intoxication and assessed confounding factors which induce delirium and extrapyramidal signs related with combination therapy of lithium and olanzapine.  相似文献   
60.
Retroperitoneal cystic lymphangioma is a rare congenital malformation. The majority of lymphangiomas are present at birth and nearly all present before the age of two years. We report a case of giant cystic retroperitoneal lymphangioma in a patient who first presented with symptoms at the age of 7, underwent surgery, and who then suffered a recurrent mass 11 years later.  相似文献   
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