In vitro comparison of the tensile bond strength of denture adhesives on denture bases.

STATEMENT OF PROBLEM: With several denture adhesives available, it is important for dentists to make appropriate patient recommendations. PURPOSE: The purpose of this study was to evaluate the tensile bond strength of denture adhesives on denture base materials at time intervals of up to 24 hours. MATERIAL AND METHODS: Fixodent, Super Poligrip, Effergrip, and SeaBond denture adhesives were tested with 3 denture base materials: 2 heat-polymerized (Lucitone 199 and SR Ivocap) and 1 visible-light-polymerized (shade-stable Eclipse). Artificial saliva with mucin was used as a control. Tensile bond strength was tested in accordance with American Dental Association specifications at 5 minutes, 3 hours, 6 hours, 12 hours, and 24 hours after applying the adhesive. Maximum forces before failure were recorded in megapascals (MPa), and the data were subjected to a 2-way analysis of variance (α=.05). RESULTS: All 4 adhesives had greater tensile bond strength than the control. Fixodent, Super Poligrip, and SeaBond had higher tensile bond strength values than Effergrip. All adhesives had the greatest tensile bond strength at 5 minutes and the least at 24 hours. The 3 denture bases produced significantly different results with each adhesive (P<.001). Lucitone 199 with the adhesives had the greatest tensile bond strength, followed by Ivocap and Eclipse. CONCLUSIONS: All 4 adhesives had greater tensile bond strength than the control, and all 4 adhesives were strongest at the 5-minute interval. On all 3 types of denture bases, Effergrip produced significantly lower tensile bond strength, and Fixodent, Super Poligrip, and SeaBond produced significantly higher tensile bond strength. At 24 hours, the adhesive-base combinations with the highest tensile bond strength were Fixodent on Lucitone 199, Fixodent on Eclipse, Fixodent on Ivocap, and Super Poligrip on Ivocap.

Sharing heterogeneous data: the national database for autism research.

The National Database for Autism Research (NDAR) is a secure research data repository designed to promote scientific data sharing and collaboration among autism spectrum disorder investigators. The goal of the project is to accelerate scientific discovery through data sharing, data harmonization, and the reporting of research results. Data from over 25,000 research participants are available to qualified investigators through the NDAR portal. Summary information about the available data is available to everyone through that portal.

Down syndrome: national conference on patient registries, research databases, and biobanks.

A December 2010 meeting, "Down Syndrome: National Conference on Patient Registries, Research Databases, and Biobanks," was jointly sponsored by the Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) at the National Institutes of Health (NIH) in Bethesda, MD, and the Global Down Syndrome Foundation (GDSF)/Linda Crnic Institute for Down Syndrome based in Denver, CO. Approximately 70 attendees and organizers from various advocacy groups, federal agencies (Centers for Disease Control and Prevention, and various NIH Institutes, Centers, and Offices), members of industry, clinicians, and researchers from various academic institutions were greeted by Drs. Yvonne Maddox, Deputy Director of NICHD, and Edward McCabe, Executive Director of the Linda Crnic Institute for Down Syndrome. They charged the participants to focus on the separate issues of contact registries, research databases, and biobanks through both podium presentations and breakout session discussions. Among the breakout groups for each of the major sessions, participants were asked to generate responses to questions posed by the organizers concerning these three research resources as they related to Down syndrome and then to report back to the group at large with a summary of their discussions. This report represents a synthesis of the discussions and suggested approaches formulated by the group as a whole.

Assessing residents in surgical ethics: we do it a lot; we only know a little.

BACKGROUND: PGY-1 year of surgical residency brings together many persons of disparate experiences and educational backgrounds, including their exposure to ethics. We hypothesized that surgical PGY-1s would have a similar exposure to ethical scenarios but lack the confidence in practice and understanding of ethical principles compared with more senior residents. MATERIALS AND METHODS: Surgical residents were invited to resident-initiated surgical ethics workshops utilizing a standardized text. Here a survey and multiple choice tests were administered to participants. The survey determined prior exposure to ethics curricula, the frequency of exposure to various ethics topics, and their comfort with these scenarios. A multiple choice test then quantified the knowledge base of participating residents. The results were collected and compared between surgical PGY-1s and more senior residents. RESULTS: Eighteen PGY-1s and 12 senior residents completed this curriculum. Resident exposure to ethical concepts was common. Resident confidence in these topics was ranked moderate or higher for both groups. Despite frequent clinical exposure and strong confidence in their skills of addressing these topics, performance on the test was poor, with an average score of 59% for PGY-1s and 47% for more senior residents (P=0.03). CONCLUSIONS: Despite clinical exposure to and confidence in their management of ethical topics, their knowledge base was poor and worse for more senior residents. Given the overall interest in a formal ethics curriculum and the knowledge deficit demonstrated, educational intervention and professional ethics support should be provided for surgical residents even with the current educational time constraints.

Designing successful removable partial dentures.

In today's busy dental offices, removable partial denture design is often abdicated by dentists, both as a result of a lack of experience and consensus of design and because of educational failure on the part of dental schools. The result is delegation of the clinical design process to the lab technician. The lack of clinical data provided to the dental technician jeopardizes the quality of care. This article will focus on a logical and simple approach to this problem, making removable partial denture design simple and predictably achievable. The clinical evidence related to removable partial denture design will be described, along with a checklist to simplify the process and make it practical and applicable to everyday clinical practice.

Real-time imaging and quantification of bioluminescent bacteria in root canals in vitro.

The detection of microorganisms in root canals is generally limited to qualitative or semiquantitative methods. We describe a new and nondestructive in vitro method to quantify root-canal bacteria over sequential treatment procedures using real-time imaging in conjunction with the bioluminescent reporter strain Pseudomonas fluorescens 5RL. Induced bacterial photon emission can be monitored by sensitive optical photonic imaging and luminometry, providing images as well as spatial and quantitative measurements. Bioluminescence imaging and luminometry determined that the lower limit of detection of bacteria in root canals occurred between 2 x 10(2) and 2 x 10(3) cells, with high correlation between cell counts and detection devices (r > or = 0.981). A preliminary study assessed the efficacy of sequential irrigation procedures to remove 5 x 10(6) bacteria from root canals (n = 5; apical size 60) using a 28-gauge, endodontic needle positioned 1 mm from working length; 9.2% +/- 3.1% and 8% +/- 3.6% of bacteria remained after 3 and 6 ml irrigation, respectively (p = 0.03), corresponding to approximately 4 x 10(5) bacteria remaining after 6 ml. This method can be used to study the efficacy of sequential endodontic treatment procedures in removing bacteria from root canals.

Clinical performance of an in-line, ex vivo point-of-care monitor: a multicenter study.

BACKGROUND: The management of critically ill infants and neonates includes frequent determination of arterial blood gas, electrolyte, and hematocrit values. An objective of attached point-of-care patient monitoring is to provide clinically relevant data without the adverse consequences associated with serial phlebotomy. METHODS: We prospectively determined the mean difference (and SD of the difference) from laboratory methods of an in-line, ex vivo monitor, the VIA LVM Blood Gas and Chemistry Monitoring System (VIA LVM Monitor; Metracor Technologies, Inc.), in 100 critically ill neonates and infants at seven children's hospitals. In doing so, we examined monitor stability with continuous use. In vivo patient test results from laboratory benchtop analyzers were compared with those from the VIA LVM Monitor on paired samples. In a separate in vitro comparison, benchtop analyzer and monitor test results were compared on whole-blood split samples. RESULTS: A total of 1414 concurrent, paired-sample measurements were obtained. The mean differences (SD of differences) from laboratory methods and r values for the combined data for the VIA LVM Monitor from the seven sites were 0.001 (0.026) and 0.97 for pH, 0.7 (3.6) mmHg and 0.94 for PCO(2), 4.2 (9.6) mmHg and 0.98 for PO(2), 0.0 (2.9) mmol/L and 0.87 for sodium, 0.1 (0.2) mmol/L and 0.96 for potassium, and 0.3% (2.9%) and 0.90 for hematocrit. Performance results were similar among the study sites with increasing time of monitor use and between in vivo paired-sample and in vitro split-sample test results. CONCLUSION: The VIA LVM Monitor can be used to assess critically ill neonates and infants.