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71.
72.

Introduction

Near-infrared diode lasers can be used for several applications, which range from disinfection to smear layer removal in endodontics. This study evaluated the efficacy of agitation of 15% EDTA with an 808-nm diode laser on removal of the smear layer.

Methods

Sixty extracted human maxillary central incisor teeth were instrumented up to ProTaper F4 (Dentsply Maillefer, Ballagues, Switzerland) and then randomly divided into 6 groups (n = 10 for each group) according to the different final irrigating protocols as follows: 5% sodium hypochlorite for 120 seconds performed with the NaviTip (Dentsply Maillefer, Ballaigues, Switzerland) (control group); 15% EDTA for 120 seconds performed with the NaviTip; and agitation of 15% EDTA with an 808-nm diode laser for 10, 20, 30, and 40 seconds. Specimens were observed under a scanning electron microscope, and open dentinal tubules were counted using Adobe Photoshop software (Adobe Systems, San Jose, CA). The data were analyzed with 1-way analysis of variance and Tukey post hoc tests (P = .05).

Results

The number of open dentinal tubules was higher in the middle thirds than in the apical thirds. The differences between the apical and middle thirds were statistically significant (P < .05). Statistically significant differences were also found between the control group and the other groups in both the middle and apical thirds of the root canals (P < .05).

Conclusions

The results indicated that agitation of 15% EDTA with an 808-nm diode laser for 20 seconds was effective in removing the smear layer in the apical thirds of root canals.  相似文献   
73.
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   
74.
Fascioliasis, which is a zoonotic infestation caused by the trematode Fasciola hepatica (liver fluke), is primarily a disease of herbivorous animals such as sheep and cattle. Humans become accidental hosts through ingesting uncooked aquatic plants such as watercress. It presents a wide spectrum of clinical pictures ranging from fever, eosinophilia and vague gastrointestinal symptoms in the acute phase to cholangitis, cholecystitis, biliary obstruction, extrahepatic infestation, or asymptomatic eosinophilia in the chronic phase. However, it may often be overlooked, especially in the acute phase, because of vague symptoms. As a result of newly introduced serological assays facilitating the diagnosis, there has been an increase in the number of reported cases. Here, we report the clinical and laboratory assessment and therapeutic approach of a series of three cases diagnosed (in order of) one week, three months and one and a half years after presentation of the first symptoms of the disease.  相似文献   
75.
Purpose:The aim of this study was to evaluate the structural and functional changes occurring in patients with branch retinal vein occlusion (BRVO) according to the distance of the affected arteriovenous (AV) crossing to the centers of the fovea and optic disc by optic coherence tomography angiography (OCTA).Methods:Forty-five patients with unilateral BRVO and 45 age- and sex-matched healthy controls were included in this retrospective observational study. Images of the macula (3 mm × 3 mm) and affected AV crossing sites were obtained by OCTA. The fovea-AV crossing distance (FAVD), optic disc-AV crossing distance (DAVD), and optic disc-fovea distance (DFD) were measured.Results:The FAVD/DFD ratio was positively correlated with the vessel density in the superficial and deep affected hemifields (r = 0.430, P < 0.05 and r = 0.308, P < 0.05, respectively) and negatively correlated with the superficial foveal avascular zone and logarithm of the minimum angle of resolution (logMAR) visual acuity (r = –0.412, P < 0.05 and r = –0.356, P < 0.05, respectively). The DAVD/DFD ratio was not correlated with the logMAR visual acuity, superficial FAZ area or vessel densities in the affected hemifield (all P > 0.05).Conclusion:The affected AV crossing site that was further away from the fovea had better visual acuity and quantitative microvascular parameters in the affected hemifields. However, this correlation was not observed for the distance between the affected AV crossing site and the optic disc.  相似文献   
76.

Purpose

To compare the healing properties of lateral internal sphincterotomy (LIS) and isosorbide dinitrate (ISDN) ointment for chronic anal fissure.

Methods

Patients with a chronic anal fissure were randomly assigned to a group treated with ISDN ointment (n = 105) or a group treated with LIS (n = 102). The same investigators examined the patients in a blinded manner, 1, 2, 3, 6, and 12 months after the treatments.

Results

The anal fissure had healed completely by 4 weeks in 64.7 versus 92.2 %, and by 6 months in 77.1 versus 97.1 % of the ISDN and LIS group patients, respectively. At 12 months, the recurrence rates were 4.8 versus 1 % for the ISDN and LIS groups, respectively, and the success rates of the treatments were 72.4 versus 96.1 %, respectively. Six patients in the LIS group experienced minor fecal incontinence, and seven (6.7 %) patients in the ISDN group experienced headaches that responded well to paracetamol.

Conclusion

ISDN ointment was reported by all patients to be easy to use. Although its success rate was lower than that of surgery, ISDN can be offered to selected patients with a chronic anal fissure, as it has a low recurrence rate and rare side effects are rare.  相似文献   
77.
Background: Covering peritoneal surfaces with soybean oil may decrease peritoneal adhesions by preventing peritoneal trauma. Method(s): Forty female albino Wistar rats were divided into four equal groups. In Group 1, soybean oil only (0.1 ml) was injected into the peritoneal cavity. In Group 2, an untreated adhesion model was generated. In Group 3, an adhesion model was generated, followed by covering the area with soybean oil (0.1 ml). In Group 4, the area was first covered with soybean oil (0.1 ml) followed by generation of an adhesion model. All rats were sacrificed on postoperative day 10, and adhesions were scored. Results: The mean macroscopic adhesion scores in Groups 1, 2, 3, and 4 were 0.0 ± 0.0, 2.90 ± 0.21, 1.90 ± 0.94, and 0.50 ± 0.71, respectively. The Group 4 score differed significantly from that of Group 2 (p <. 001), but was not different from that of Group 1 or 3 (p >. 05). Discussion: Soybean oil can effectively decrease adhesion formation if applied before peritoneal trauma.  相似文献   
78.
Over the last decade, developments in technology have led a rapid progress in robotic endocrine surgery applications. Robotics is attractive to the surgeon because of the three-dimensional image quality, articulating instruments, and stable surgical platform. Safety and effectiveness of robotic adrenalectomy and thyroidectomy have been shown in many studies. While these robotic procedures offer better ergonomics for the surgeon, they provide similar outcomes compared to the laparoscopic approach for adrenalectomy and better cosmetic results versus the conventional option for thyroidectomy. Recently, while the robotic approach for adrenalectomy has been popularized, enthusiasm for robotic thyroidectomy has decreased. In the present review we aim to describe emerging robotic procedures and review the literature regarding outcomes.  相似文献   
79.
PurposeExcision repair cross-complementation group 1 enzyme (ERCC1) plays a key role in the removal of platinum induced DNA adducts and cisplatin resistance. Prognostic role of ERCC1 expression in the neoadjuvant setting in bladder cancer has not been reported before. We evaluated the prognostic role of ERCC1 expression in bladder cancer receiving platinum-based neoadjuvant chemotherapy.Materials and methodsThirty-eight patients with muscle invasive bladder cancer who received neoadjuvant platinum-based chemotherapy were included. Clinical and histopathologic parameters along with immunohistochemical ERCC1 staining were examined and correlated with response rates and survival.ResultsPathologic complete response rates were similar between patients with low and high ERCC1 expression. Median disease-free survival (DFS) was 9.3 vs. 20.5 months (P = 0.186) and median overall survival (OS) was 9.3 vs. 26.7 months (P = 0.058) in patients with high ERCC1 expression compared with those with low expression, respectively. In multivariate Cox regression analysis: pathological complete response (pCR) after chemotherapy (hazard ratio (HR) 0.1, 95% CI 0.012–0.842, P = 0.034) and high ERCC1 expression (HR 3.7, 95% CI 1.2–11.2, P = 0.019) were significantly associated with DFS. Patient age (>60 vs. ≤60 years) (HR 3.4, 95% CI 1.2–9.4, P = 0.018), the presence of pCR (HR 0.11, 95% CI 0.014–0.981, P = 0.048) and high ERCC expression (HR 6.1, 95 CI 1.9–19.9, P = 0.002) were significantly associated with OS.ConclusionsOur results showed that high ERCC1 expression was independently associated with shorter disease-free and overall survival in patients with bladder cancer who received neoadjuvant platinum-based chemotherapy. ERCC1 may represent a potential predictive marker for platinum-based treatment in bladder cancer.  相似文献   
80.
This study investigated the effect of Ankaferd Blood Stopper (ABS) contamination on bond strength of total- and self-etching systems. Seventy mandibular third molars sectioned in a mesio-distal direction were mounted in acrylic resin, and flat dentin surfaces were exposed. The specimens were randomly assigned to seven groups (n=20), according to the surface treatment: Group I, ABS contamination+37% phosphoric acid+Solobond M; Group II, ABS contamination+Clearfil SE Bond; Group III, ABS contamination+All Bond SE; Group VI, 37% phosphoric acid+ABS contamination+Solobond M; Group V, Solobond M; Group VI, Clearfil SE Bond; and Group VII, All Bond SE. Next, a resin composite (Grandio) was built up using a plastic apparatus and polymerized. The specimens were tested in shear mode at a crosshead speed of 1 mm/min. There were significant differences in bond strengths between the control and ABS-contaminated samples. These findings suggest that ABS contamination reduced bond strength of total- and self-etching adhesives.  相似文献   
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