56-month clinical performance of Class I and II resin composite restorations

Objective: This study evaluated the 56-month clinical performance of Class I and II resin composite restorations. Filtek P60 was compared with Filtek Z250, which are both indicated for posterior restorations but differ in terms of handling characteristics. The null hypothesis tested was that there is no difference in the clinical performance of the two resin composites in posterior teeth. Material and Methods: Thirty-three patients were treated by the same operator, who prepared 48 Class I and 42 Class II cavities, which were restored with Single Bond/Filtek Z250 or Single Bond/Filtek P60 restorative systems. Restorations were evaluated by two independent examiners at baseline and after 56 months, using the modified USPHS criteria. Data were analyzed statistically using Chi-square and Fisher's Exact tests (alpha=0.05). Results: After 56 months, 25 patients (31 Class I and 36 Class II) were analyzed. A 3% failure rate occurred due to secondary caries and excessive loss of anatomic form for P60. For both restorative systems, there were no significant differences in secondary caries and postoperative sensitivity. However, significant changes were observed with respect to anatomic form, marginal discoloration, and marginal adaptation. Significant decreases in surface texture were observed exclusively for the Z250 restorations. Conclusions: Both restorative systems can be used for posterior restorations and can be expected to perform well in the oral environment.

Optimized Duration of Clopidogrel Therapy Following Treatment with the Endeavor Zotarolimus-Eluting Stent in Real-World Clinical Practice (OPTIMIZE) Trial: Rationale and design of a large-scale, randomized, multicenter study

Background Current recommendations for antithrombotic therapy after drug-eluting stent (DES) implantation include prolonged dual antiplatelet therapy (DAPT) with aspirin and clopidogrel >= 12 months. However, the impact of such a regimen for all patients receiving any DES system remains unclear based on scientific evidence available to date. Also, several other shortcomings have been identified with prolonged DAPT, including bleeding complications, compliance, and cost. The second-generation Endeavor zotarolimus-eluting stent (E-ZES) has demonstrated efficacy and safety, despite short duration DAPT (3 months) in the majority of studies. Still, the safety and clinical impact of short-term DAPT with E-ZES in the real world is yet to be determined. Methods The OPTIMIZE trial is a large, prospective, multicenter, randomized (1: 1) non-inferiority clinical evaluation of short-term (3 months) vs long-term (12-months) DAPT in patients undergoing E-ZES implantation in daily clinical practice. Overall, 3,120 patients were enrolled at 33 clinical sites in Brazil. The primary composite endpoint is death (any cause), myocardial infarction, cerebral vascular accident, and major bleeding at 12-month clinical follow-up post-index procedure. Conclusions The OPTIMIZE clinical trial will determine the clinical implications of DAPT duration with the second generation E-ZES in real-world patients undergoing percutaneous coronary intervention. (Am Heart J 2012;164:810-816.e3.)

Clinical evaluation of ceramic inlays and onlays fabricated with two systems: five-year follow-up

This study evaluated the five-year clinical performance of ceramic inlays and onlays made with two systems: sintered Duceram (Dentsply-Degussa) and pressable IPS Empress (Ivoclar Vivadent). Eighty-six restorations were placed by a single operator in 35 patients with a median age of 33 years. The restorations were cemented with dual-cured resin cement (Variolink II, Ivoclar Vivadent) and Syntac Classic adhesive under rubber dam. The evaluations were conducted by two independent investigators at baseline, and at one, two, three, and five years using the modified United States Public Health Service (USPHS) criteria. At the five-year recall, 26 patients were evaluated (74.28%), totalling 62 (72.09%) restorations. Four IPS restorations were fractured, two restorations presented secondary caries (one from IPS and one from Duceram), and two restorations showed unacceptable defects at the restoration margin and needed replacement (one restoration from each ceramic system). A general success rate of 87% was recorded. The Fisher exact test revealed no significant difference between Duceram and IPS Empress ceramic systems for all aspects evaluated at different recall appointments (p>0.05). The McNemar chi-square test showed significant differences in relation to marginal discoloration, marginal integrity, and surface texture between the baseline and five-year recall for both systems (p<0.001), with an increased percentage of Bravo scores. However, few Charlie or Delta scores were attributed to these restorations. In conclusion, these two types of ceramic materials demonstrated acceptable clinical performance after five years

Human toxocariasis: diagnosis, worldwide seroprevalences and clinical expression of the systemic and ocular forms.

Although human toxocariasis ranks among the most common zoonotic infections worldwide, it remains relatively unknown to the public. The causal agents are the nematode parasites Toxocara canis and T. cati, whose definitive hosts are dogs and cats, respectively. When embryonated eggs are accidentally ingested by humans, larvae hatch in the small intestine, penetrate the intestinal wall and migrate, via the bloodstream, to the liver, lungs, muscles, eye and central nervous system. Although most human infections are asymptomatic, two well-defined clinical syndromes are classically recognised: visceral larva migrans (a systemic disease caused by larval migration through major organs) and ocular larva migrans (a disease limited to the eyes and optic nerves). Two less-severe syndromes have recently been described, one mainly in children (covert toxocariasis) and the other mainly in adults (common toxocariasis). Here, the current laboratory diagnosis, epidemiology and main clinical features of both the systemic and ocular forms of human toxocariasis are reviewed. New developments in serological diagnosis are described, the available seroprevalence data are analysed, and the results of relevant clinical studies that have been published over the last decade are explored, to provide an updated overview of this neglected but highly prevalent human infection.

Analysis of genetic lineages and their correlation with virulence genes in enterococcus faecalis clinical isolates from root canal and systemic infections

Introduction: Enterococcus faecalis is a member of the mammalian gastrointestinal microbiota but has been considered a leading cause of hospital-acquired infections. In the oral cavity, it is commonly detected from root canals of teeth with failed endodontic treatment. However, little is known about the virulence and genetic relatedness among E. faecalis isolates from different clinical sources. This study compared the presence of enterococcal virulence factors among root canal strains and clinical isolates from hospitalized patients to identify virulent clusters of E. faecalis. Methods: Multilocus sequence typing analysis was used to determine genetic lineages of 40 E. faecalis clinical isolates from different sources. Virulence clusters were determined by evaluating capsule (cps) locus polymorphisms, pathogenicity island gene content, and antibiotic resistance genes by polymerase chain reaction. Results: The clinical isolates from hospitalized patients formed a phylogenetically separate group and were mostly grouped in the clonal complex 2, which is a known virulent cluster of E. faecalis that has caused infection outbreaks globally. The clonal complex 2 group comprised capsule-producing strains harboring multiple antibiotic resistance and pathogenicity island genes. On the other hand, the endodontic isolates were more diverse and harbored few virulence and antibiotic resistance genes. In particular, although more closely related to isolates from hospitalized patients, capsuleproducing E. faecalis strains from root canals did not carry more virulence/antibiotic genes than other endodontic isolates. Conclusions: E. faecalis isolates from endodontic infections have a genetic and virulence profile different from pathogenic clusters of hospitalized patients’ isolates, which is most likely due to niche specialization conferred mainly by variable regions in the genome.

Usefulness of clinical findings, nerve conduction studies and ultrasonography to predict response to surgical release in idiopathic carpal tunnel syndrome.

[EN] OBJECTIVES: To assess the usefulness of clinical findings, nerve conduction studies and ultrasonography performed by a rheumatologist to predict success in patients with idiopathic carpal tunnel syndrome (CTS) undergoing median nerve release. METHODS: Ninety consecutive patients with CTS (112 wrists) completed a specific CTS questionnaire and underwent physical examination and nerve conduction studies. Ultrasound examination was performed by a rheumatologist who was blind to any patient's data. Outcome variables were improvement >25% in symptoms of the CTS questionnaire and patient's overall satisfaction (5-point Likert scale) at 3 months postoperatively. Success was defined as improvement in both outcome variables. Receiver operating characteristics (ROC) curves and logistic regression analyses were used to assess the best predictive combination of preoperative findings. RESULTS: Success was achieved in 63% of the operated wrists. Utility parameters and area under the ROC curve (AUC) for individual findings was poor, ranging from 0.481 of the nerve conduction study to 0.634 of the cross-sectional area at tunnel outlet. Logistic regression identified the preoperative US parameters as the best predictive variables for success after 3 months. The best predictive combination (AUC=0.708) included a negative Phalen maneuver, plus absence of thenar atrophy, plus less than moderately abnormalities on nerve conduction studies plus a large maximal cross-sectional area along the tunnel by ultrasonography. CONCLUSION: Although cross-sectional area of the median nerve was the only predictor of success after three months of surgical release, isolated preoperative findings are not reliable predictors of success in patients with idiopathic CTS. A combination of findings that include ultrasound improves prediction.

Essays in Applied and Labor Economics

This thesis consists of three self-contained papers. In the first paper I analyze the labor supply behavior of Bologna Pizza Delivery Vendors. Recent influential papers analyze labor supply behavior of taxi drivers (Camerer et al., 1997; and Crawford and Meng, 2011) and suggest that reference-dependence preferences have an important influence on drivers’ labor-supply decisions. Unlike previous papers, I am able to identify an exogenous and transitory change in labor demand. Using high frequency data on orders and rainfall as an exogenous demand shifter, I invariably find that reference-dependent preferences play no role in their labor’ supply decisions and the behavior of pizza vendors is perfectly consistent with the predictions of the standard model of labor’ supply. In the second paper, I investigate how the voting behavior of Members of Parliament is influenced by the Members seating nearby. By exploiting the random seating arrangements in the Icelandic Parliament, I show that being seated next to Members of a different party increases the probability of not being aligned with one’s own party. Using the exact spatial orientation of the peers, I provide evidence that supports the hypothesis that interaction is the main channel that explain these results. In the third paper, I provide an estimate of the trade flows that there would have been between the UK and Europe if the UK had joined the Euro. As an alternative approach to the standard log-linear gravity equation I employ the synthetic control method. I show that the aggregate trade flows between Britain and Europe would have been 13% higher if the UK had adopted the Euro.

Stochastic foundations of dynamic trade and labor market models

This dissertation consists of three self-contained papers that are related to two main topics. In particular, the first and third studies focus on labor market modeling, whereas the second essay presents a dynamic international trade setup.rnrnIn Chapter "Expenses on Labor Market Reforms during Transitional Dynamics", we investigate the arising costs of a potential labor market reform from a government point of view. To analyze various effects of unemployment benefits system changes, this chapter develops a dynamic model with heterogeneous employed and unemployed workers.rn rnIn Chapter "Endogenous Markup Distributions", we study how markup distributions adjust when a closed economy opens up. In order to perform this analysis, we first present a closed-economy general-equilibrium industry dynamics model, where firms enter and exit markets, and then extend our analysis to the open-economy case.rn rnIn Chapter "Unemployment in the OECD - Pure Chance or Institutions?", we examine effects of aggregate shocks on the distribution of the unemployment rates in OECD member countries.rn rnIn all three chapters we model systems that behave randomly and operate on stochastic processes. We therefore exploit stochastic calculus that establishes clear methodological links between the chapters.

Standardized definitions and clinical endpoints in carotid artery and supra-aortic trunk revascularization trials

Endovascular therapy has emerged as a promising alternative to open surgery for stroke prevention in patients with obstructive disease of the supra-aortic arteries. Although most previous studies have used similar safety and efficacy endpoints, differences in definitions, timing of assessments, and standards of reporting have hampered direct comparisons across various trials.

Nutritional risk is a clinical predictor of postoperative mortality and morbidity in surgery for colorectal cancer

This study investigated whether nutritional risk scores applied at hospital admission predict mortality and complications after colorectal cancer surgery.

Influence of examiner's clinical experience on the reproducibility and accuracy of radiographic examination in detecting occlusal caries

The aim of this in vitro study was to assess the influence of varying examiner's clinical experience on the reproducibility and accuracy of radiographic examination for occlusal caries detection. Standardized bitewing radiographs were obtained from 166 permanent molars. Radiographic examination was performed by final-year dental students from two universities (A, n = 5; B, n = 5) and by dentists with 5 to 7 years of experience who work in two different countries (C, n = 5; D, n = 5). All examinations were repeated after 1-week interval. The teeth were histologically prepared and assessed for caries extension. For intraexaminer reproducibility, the unweighted kappa values were: A (0.11-0.40), B (0.12-0.33), C (0.47-0.58), and D (0.42-0.71). Interexaminer reproducibility statistics were computed based on means ± SD of unweighted kappa values: A (0.07 ± 0.05), B (0.12 ± 0.09), C (0.24 ± 0.08), and D (0.33 ± 0.10). Sensitivity, specificity, and accuracy were calculated at D(1) and D(3) thresholds and compared by performing McNemar test (p = 0.05). D(1) sensitivity ranged between 0.29 and 0.75 and specificity between 0.24 and 0.85. D(3) specificity was moderate to high (between 0.62 and 0.95) for all groups, with statistically significant difference between the dentists groups (C and D). Sensitivity was low to moderate (between 0.21 and 0.57) with statistically significant difference for groups B and D. Accuracy was similar for all groups (0.55). Spearman's correlations were: A (0.12), B (0.24), C (0.30), and D (0.38). In conclusion, the reproducibility of radiographic examination was influenced by the examiner's clinical experience, training, and dental education as well as the accuracy in detecting occlusal caries.