Shear bond strength of AH-26 and Epiphany to composite resin and Resilon

The aim of this study was to evaluate the relative bond strengths of AH-26 and Epiphany sealers to both Resilon and composite resin. Four groups of substrate/bonded sealer combinations were tested: group A, composite resin substrate + Epiphany sealer; group B, composite resin substrate + AH-26 sealer; group C, Resilon substrate + Epiphany sealer; and group D, Resilon substrate + AH-26 sealer. Bond strength was evaluated in shear mode by using a universal testing machine at a crosshead speed of 0.5 mm/min. Statistical analysis (Kruskall-Wallis and Dunn tests) showed that the bond strength of AH-26 to both substrates was significantly greater than the bond strength of Epiphany. Therefore, the monoblock in the root canal might be more effectively achieved by combining Resilon core material with the epoxy resin-based sealer (AH-26) rather than Epiphany sealer.     

Torque expression of self-ligating brackets compared with conventional metallic, ceramic, and plastic brackets

The purpose of this research was to investigate the torque capacity of active and passive self-ligating brackets compared with metallic, ceramic, and polycarbonate edgewise brackets. Six types of orthodontic brackets were included in the study: the self-ligating Speed and Damon2, the stainless steel (SS), Ultratrimm and Discovery, the ceramic bracket, Fascination 2, and the polycarbonate bracket, Brillant. All brackets had a 0.022-inch slot size and were torqued with 0.019 x 0.025-inch SS archwires. For this purpose, the labial crown torque of an upper central incisor was measured in a simulated intraoral clinical situation using the orthodontic measurement and simulation system (OMSS). A torque of 20 degrees was applied and the correction of the misalignement was simulated experimentally with the OMSS. Each bracket/wire combination was measured five times. Maximum torquing moments and torque loss were determined. The results were analysed with one-way analysis of variance, with the bracket serving as the sole discriminating variable, and the Tukey test at the 0.05 level of significance. The ceramic bracket (Fascination 2) presented the highest torquing moment (35 Nmm) and, together with a SS bracket, the lowest torque loss (4.6 degrees). Self-ligating, polycarbonate, and selective metallic brackets demonstrated almost a 7-fold decreased moment developed during insertion of a 0.019 x 0.022-inch SS wire into a 0.022-inch slot and a 100 per cent increase in loss.     

Complications of intrastromal corneal ring segment implantation using a femtosecond laser for channel creation: a survey of 850 eyes with keratoconus

Acta Ophthalmol. 2011: 89: 54–57

Abstract.

Purpose: To report complications after the implantation of intrastromal corneal ring segments (Keraring; Mediphacos, Belo Horizonte, Brazil) in keratoconic eyes using a femtosecond laser (IntraLase; Advanced Medical Optics, Santa Ana, California, USA) for channel creation. Methods: Retrospective chart review of 531 patients (850 eyes) who underwent Keraring insertion using a femtosecond laser for channel creation. Intraoperative and postoperative complications were recorded. Results: Intraoperatively, there were 22 (2.7%) cases of incomplete channel formation. The rest of the intraoperative complications were galvo lag error (system malfunction) [five eyes (0.6%)], endothelial perforation [five eyes (0.6%)] and incorrect entry of the channel [two eyes (0.2%)]. Postoperatively, there were 11 (1.3%) cases of segment migration, two (0.2%) cases of corneal melting and one (0.1%) case of mild infection. The overall complication rate was 5.7% (49 cases out of 850 eyes). Conclusion: In this study, intracorneal ring segment implantation using a femtosecond laser for channel creation was related to a number of complications. The most common complications were incomplete channel creation (intraoperatively) and segment migration (postoperatively).     

Biological studies of new organotin(IV) complexes of thioamide ligands

New organotin(IV) complexes with heterocyclic thioamides 2-mercapto-benzothiazole (Hmbzt), 5-chloro-2-mercapto-benzothiazole (Hcmbzt) and 2-mercapto-benzoxazole (Hmbzo) of formulae [(C(6)H(5))(3)Sn(mbzt)] (1), [(C(6)H(5))(3)Sn(cmbzt)] (3) and [(C(6)H(5))(2)Sn(cmbzt)(2)] (4), together with the already known [(C(6)H(5))(3)Sn(mbzo)] (2), [(n-C(4)H(9))(2)Sn(cmbzt)(2)] (5) and [(CH(3))(2)Sn(cmbzt)(2)] (6) were used to study their influence on the peroxidation of oleic acid. The influence of complexes (3)-(6) upon peroxidation of oleic acid showed that the formation of reactive radicals caused the initiation of the chain radical oxidation of the substrate. The influence of complexes (1)-(6) upon the catalytic peroxidation of linoleic acid by the enzyme lipoxygenase (LOX) was also studied and compared to those of cisplatin. Compounds (1)-(6) were finally tested for in vitro cytotoxicity against leiomyosarcoma cells.     

Peroneal nerve damage by bicortical tibial screw in ACL reconstruction

Arthroscopically assisted anterior cruciate ligament reconstruction is regarded as a minimally invasive surgery with low morbidity but complications still occur. Reports of neurovascular injuries related to graft harvesting, tunnel placement, or graft fixation are limited. A rare case of peroneal nerve injury related to hardware used for graft fixation in the tibial in a 28-year-old female patient who underwent an anterior cruciate ligament reconstruction surgery using a patellar tendon graft (bone-tendon-bone graft) is presented. Post-operatively, the patient presented with clinical signs of peroneal nerve damage and a reduced range of motion of the knee. Plain radiographs of the knee showed the bicortical screw which used for tibial fixation of the graft, penetrating the fibula and projecting beyond the lateral cortex of the fibular neck. The patient was treated with removal of the hardware and the graft. Intensive physiotherapy resulted in gradual improvement and at 6 months after the second operation the patient regained full range of motion of the knee and almost full muscle strength performing her daily activities without any difficultly and she is at the moment unwilling to undergo further procedure.     

Thrombophilic risk factors in the pathogenesis of non-arteritic anterior ischemic optic neuropathy patients

Background  

Non-arteritic anterior ischemic optic neuropathy (N-AION) is caused by acute ischemic infarction of the optic nerve head, supplied by the posterior ciliary arteries. Thrombophilia is the tendency/predisposition to vascular thromboses of arteries and veins, and the existence of thrombophilic risk factors leads to blood hypercoagulability and potentially increased risk for thromboses.     

Favorable clinical course of patients experiencing bevacizumab-induced proteinuria

Nephrotic-range proteinuria, which denotes structural damage to the glomerular filtration barrier, occurs in 1-2% of bevacizumab-treated patients. The glomerular injury and subsequent proteinuria is probably due to a direct targeting of vascular endothelial growth factor (VEGF). We report a case series of six patients who developed a syndrome characterized by proteinuria and hypertension after starting therapy with bevacizumab and who experienced prolonged progression-free survival. Given that altered glomerular permeability appears to be a direct consequence of VEGF inhibition, we hypothesize that proteinuria may indeed correlate with drug efficacy. Optimizing safe and effective drug dosing is critical to achieve the best therapeutic impact due to limited treatment options for many life-threatening advanced cancers. Clinicians should be aware that the development of proteinuria might serve as a surrogate marker of bevacizumab antitumor efficacy and determine the appropriate criteria for withholding this effective anticancer therapy.     

Port central venous catheters–associated bloodstream infection during outpatient-based chemotherapy

Central venous catheters (CVCs) are commonly used for the administration of intravenous chemotherapy in outpatient setting. Nevertheless, outbreaks of catheter-associated bloodstream infections had been reported from oncology centers. We describe a large outbreak of CVCs-associated Klebsiella oxytoca bloodstream infection, occurring in an oncology chemotherapy outpatient unit of northern Greece between October 2006 and May 2007. The outbreak involved approximately 10% of the patients with CVCs who were receiving home-based chemotherapy, and it represents the second larger outbreak of CVCs-associated BSIs due to Klebsiella oxytoca in oncology outpatient centers. We retrospectively analyzed the chain of investigations and prophylactic/diagnostic measures taken to eradicate the infection: (1) patients’ chart audit, (2) estimation of the infection among asymptomatic patients, (3) implementation of the level of awareness of medical and paramedical personnel, (4) collection of samples from environment, medications and infusion materials, (5) critical appraisal of chemotherapeutical schemes and (6) cooperation with peripheral institutions. The isolation of Klebsiella oxytoca in a chemotherapy solution (infusional 5-FU in dextrose 5% solution within a 48 h pump) from a peripheral General Hospital and the prompt transmission of the data to the chemotherapy center played a key role for the management of the infection cluster. This is the first report that evidenced the detection of Klebsiella oxytoca within a chemotherapeutical preparation. Data transmission from peripheral hospitals to the central institution resulted in an important feedback that allowed a better estimation of the infection cluster and more tailored actions for the eradication of the infection.