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Being able to test for the presence of blood pathogens at forward locations could reduce morbidity and mortality in the field. Rapid, user-friendly blood typing kits for detecting Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV), and Hepatitis B Virus (HBV) were evaluated to determine their accuracy after storage at various temperatures/humidities. Rates of positive tests of control groups, experimental groups, and industry standards were compared (Fisher's exact χ², p ≤ 0.05). Compared to the control group, 2 of 10 HIV detection devices were adversely affected by exposure to high temperature/high humidity or high temperature/low humidity. With one exception, none of the environmentally exposed HCV or HBV detection devices exhibited significant differences compared to those stored under control conditions. For HIV, HCV, and HBV devices, there were differences compared to the industry standard. Collectively, this evaluation of pathogen detection kits revealed that diagnostic performance varies among products and storage conditions, and that the tested products cannot be considered to be approved for use to screen blood, plasma, cell, or tissue donors. [ABSTRACT FROM AUTHOR]

Rapid user-friendly ABO-Rh blood typing kits (Eldon Home Kit 2511, ABO-Rh Combination Blood Typing Experiment Kit) were evaluated to determine their accuracy when used under simulated military field conditions and after long-term storage at various temperatures and humidities. Rates of positive tests between control groups, experimental groups, and industry standards were measured and analyzed using the Fisher's exact chi-square method to identify significant differences (p ≤ 0.05). When Eldon Home Kits 2511 were used in various operational conditions, the results were comparable to those obtained with the control group and with the industry standard. The performance of the ABO-Rh Combination Blood Typing Experiment Kit was adversely affected by prolonged storage in temperatures above 37°C. The diagnostic performance of commercial blood typing kits varies according to product and environmental storage conditions. [ABSTRACT FROM AUTHOR]

A significant problem with most field dental units is that their suction is too weak to effectively remove debris from the mouth. The purpose of this study was to determine the minimum clinically acceptable suction level for routine dentistry. A vacuum pump was connected to a high-volume dental evacuation line in a simulated clinical setting and different suction airflow rates were evaluated by nine evaluator dentists for their capability to effectively remove amalgam debris and water. Airflow levels were rated as "clinically acceptable" or "clinically unacceptable" by each evaluator. Data were analyzed using a chi2 test for trend. Analysis indicated a significant linear trend between airflow and ratings (p < 0.0001). The first airflow level considered by all evaluators as producing clinically acceptable suction was 4.5 standard cubic feet per minute (0.127 standard cubic meters per minute). This value should be the minimum level required for all military field dental units. [ABSTRACT FROM AUTHOR]

The purpose of this study was to measure select properties of four temporary filling materials suitable for use in treating minor dental emergencies in the field. Specimens were made of each of the following four materials: intermediate restorative material, Fuji IX GP Fast, Ketac-Molar Quick, and the forward-deployable dental dressing recently developed by the Naval Institute for Dental and Biomedical Research. Twenty-four hours after specimen fabrication, five properties (hardness, compressive strength, diamentral tensile strength, flexural strength, and flexural modulus) were measured for each of the materials and compared using analysis of variance and Tukey-Kramer tests to determine whether significant differences existed among the materials (α = 0.05). Data analysis revealed that significant differences existed among the products for all of the properties tested. The forward-deployable dental dressing's properties compared favorable with and, in many cases exceeded those of intermediate restorative material. Fuji IX GP Fast, and Ketac-Molar Aplicap Quick. [ABSTRACT FROM AUTHOR]

The purpose of this work was to evaluate the clinical performance of a number of types of field (i.e., portable) dental equipment used under actual military deployment conditions. This equipment is often used under demanding field conditions where temperature, humidity, and air quality are not controlled. This article presents the results of a project conducted by the Naval Institute for Dental and Biomedical Research and the Air Force Dental Evaluation and Consultation Service to evaluate commercially available field dental equipment through laboratory testing and clinical user evaluations at military deployment sites. The purpose of the study was to identify the best-performing and most cost-effective field dental equipment for possible operational use by the U.S. Navy. Initial laboratory testing was performed at the Naval Institute for Dental and Biomedical Research and the equipment was then shipped to Okinawa, Japan, where it was tested by military dentists and assistants under deployment conditions. The testing provided beneficial results by identifying equipment that performed properly and equipment that exhibited shortcomings serious enough to render it inappropriate for field use. [ABSTRACT FROM AUTHOR]

Dental officers and technicians must have reliable, durable, well-performing field dental equipment to enable them to provide dental care to deployed troops in operational environments. Unfortunately, no organized program exists to test such equipment before its purchase and use in the field. This article presents the results of a project conducted by the Naval Institute for Dental and Biomedical Research and the Air Force Dental Evaluation and Consultation Service to evaluate commercially available field dental equipment through laboratory testing and clinical-user evaluations in theater. The purpose of this 2-year project was to identify the best-performing and most cost-effective field dental equipment for possible future procurement. Initial laboratory testing was performed at the Naval Institute for Dental and Biomedical Research, and the equipment was then shipped to Kuwait for in-theater environmental and clinical-user testing. A seven-member scientific team of military dental officers and technicians was deployed for 1 month to perform in-theater testing under regional environmental conditions and to coordinate clinical-user evaluations. The testing provided beneficial results by identifying equipment that performed properly and equipment that exhibited shortcomings serious enough to render it inadequate for operational use. It is recommended that the project serve as a model for future testing and evaluation of medical/dental equipment by all of the military services. [ABSTRACT FROM AUTHOR]

Summary: Objectives: The purpose of this study was to measure the polymerization shrinkage of three dental resin composites using two commercially available video-imaging devices to determine if the devices produced equivalent results. Methods: Small, semi-spherical specimens of a microhybrid (Venus), microfill (Filtek A110), and flowable (Esthet•X Flow) resin composite were manually formed and light activated for 40s using a light-curing unit. The volumetric polymerization shrinkage of fifteen specimens of each brand of resin composite was measured using the AcuVol and the Drop Shape Analysis System model DSA10 Mk2 (DSAS) video-imaging devices. Mean volumetric shrinkage values were calculated for each resin composite and equivalence was evaluated using the two one-sided tests approach. Differences between the means that were less than approximately 5% of the observed shrinkage were considered indicative of clinical equivalence. Results: Mean volumetric shrinkage values measured for the resin composites were: Venus (AcuVol, 3.07±0.07%; DSAS, 2.90±0.07%); Filtek A110 (AcuVol, 2.26±0.10%; DSAS, 2.25±0.09%); and Esthet•X Flow (AcuVol, 5.01±0.17%; DSAS, 5.14±0.11%). Statistical analysis revealed that the two imaging devices produced equivalent results for Filtek A110 and Esthet•X Flow but not for Venus. Conclusions: Video-imaging systems provide an easy method for measuring volumetric shrinkage of resin composites. As with other methods for measuring volumetric shrinkage, however, they are best used to comparatively measure different materials within the same laboratory. [Copyright &y& Elsevier]

Focuses on a study which compared the curing efficiency of several commercially available light-emitting diode (LED)-based curing lights with that of a quartz tungsten halogen curing light by means of hardness testing. Advantages of LED technology over halogen lights in curing a microfill resin composite; Results of the testing of curing efficiency; Measurement of power density.

Describes the electroweak physics at LEP machine. Use of standard model; Fermion-pair production; Presence of Z resonance at lower center-of-mass energies; Four-fermion contact interaction to electroweak scale quantum gravity; Average W decay branching ratio measurements.

To help preserve in-theater strength within deployed military units, commercially available, rapid, user-friendly ABO-Rh blood typing kits were evaluated to determine their stability in storage conditions commonly encountered by the warfighter. Methods for environmental exposure testing were based on MIL-STD-810E When Eldon Home Kits 2511 were exposed to various temperature/relative hudaidity conditions, the results were comparable to those obtained with the control group and those obtained with industry-standard methods. For the ABO-Rh Combination Blood Typing Experiment Kits, 2 of the exposure treatments rendered them unusable. In addition, a third set of exposure treatments adversely affected the kits, resulting in ~30% blood type misclassifications. Collectively, this evaluation of commercial blood typing kits revealed that diagnostic performance can vary between products, lots, and environmental storage conditions. [ABSTRACT FROM AUTHOR]

Statement of the Problem: The polymerization of bulk-placed resin-modified glass-ionomer (RMGI) restoratives is compromised when penetration of the curing light is limited because of the materials' thickness. It is unknown if additional post light-curing resin polymerization and/or glass-ionomer setting occurs over time to ensure adequate polymerization. Purpose: The primary objective was to evaluate the depth of cure of various thicknesses of RMGI restorative products over 1 year using Knoop hardness (KH) testing. Materials and Methods: The materials were placed in Delrin molds having an internal diameter of 5.0 mm and heights of 2, 3, 4, and 5 mm and were photopolymerized with a halogen light-curing unit. Five specimens of each depth were prepared for each time period evaluated. Specimens were stored in darkness at 37 ± 2°C and 98 ± 2% humidity until being tested at 24 hours, 1 week, and 1, 3, 6, 9, and 12 months after fabrication. Mean KH values were calculated for the bottom and top surfaces of each thickness group and used to determine bottom/top hardness ratios. Data were compared using two-way analysis of variance (factors of time, thickness) at a 0.05 significance level with Scheffé's post hoc analysis, where required. Results: The materials had relatively stable top surface KH, which permitted valid assessment of changes in bottom surface KH over time. The bottom surface KH of some RMGIs changed significantly over time ( p < 0.001), but degrees of change were material dependent. Certain RMGIs demonstrated a potential for statistically significant post light-activation hardening; however, that too was material dependent. As compared with top surface KH, deeper layers of the thicker RMGI specimens consistently failed to achieve an adequate degree of polymerization. Conclusion: Although certain RMGI materials demonstrate a potential for post light-activation chemically initiated resin polymerization and/or polyalkenoate acid/base reaction, these reactions may not be sufficient to ensure that the material is adequately polymerized for long-term success. This is particularly true when RMGI materials are placed in thicker layers where curing light penetration may be compromised. CLINICAL SIGNIFICANCE RMGI materials should not be placed in bulk but photopolymerized in layers to ensure adequate light activation. The results of this study suggest that Photac-Fil Quick be placed in layers no thicker than 2 mm while Fuji II LC and Vitremer may be placed in layers up to 3 mm in thickness. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To investigate the effect of two glass-polyalkenoate restorative materials used as root-dentin replacements on the fracture strength of Class II amalgam restorations. Materials and methods: Class II slot preparations extending 2mm apical to the cemento-enamel junction were made in 30 teeth and randomly assigned to three groups. Group 1 (Control): restored entirely with amalgam (Tytin, Sybron Kerr, Orange, CA, USA). Group 2: The root-dentin area was restored with a viscous conventional glass-polyalkenoate restorative material (Fuji IX GP, GC America, Alsip, IL, USA), and the remainder of the preparation restored with amalgam. Group 3: The root-dentin area was restored with a resin-modified glass-polyalkenoate restorative material (Fuji II LC, GC America) and the remainder restored with amalgam. The amalgam restorations were loaded in compression to failure and the data analyzed using one-way ANOVA (α =0.05). Results: No significant differences in fracture strength were found. Conclusion: Root-dentin replacement with the tested glass-polyalkenoate materials did not affect the fracture strength of Class II amalgam restorations. [Copyright &y& Elsevier]

With respect to determining sub-surface resin polymerization sufficiency, this study compared a traditional method of applying linear regression to bottom- to top-surface Knoop hardness ratios to an alternative method based on nonlinear regression. Inverse linear regression on ratios was used to estimate the exposure duration required for 80% bottom-surface hardness with respect to the top, in six light-by-material groups. Alternatively, a one-phase, two-parameter, exponential association of the form Y=Ymax(1−e−kt) (where Ymax is maximum hardness, k is a rate constant, and t is exposure duration), was used to model hardness. Inverse nonlinear regression estimated, for each condition, the exposure duration required for the bottom surface to achieve 80% of corresponding condition (light and material) top-surface Ymax. Mathematically, analysis of ratios was demonstrated to yield potentially less precise and biased estimates. Nonlinear regression yielded better statistical fit and provided easily accessible tests for differences in k across light-system groups. Another recently proposed nonlinear model for polymerization, Y=Ymaxktn/(1+ktn), was also considered. While this new model has substantially greater phenomenological and mechanistic justification, we found that the model-fitting process was more sensitive to initial parameter values and sometimes yielded untenable results when applied to our data. However, we believe that these problems would not occur if sample points are well distributed across a wide range of exposure durations, and that the model, Y=Ymaxktn/(1+ktn), should be considered for such data sets. [Copyright &y& Elsevier]

Being able to test for the presence of blood pathogens at forward locations could reduce morbidity and mortality in the field. Rapid, user-friendly blood typing kits for detecting Human Immunodeficiency Virus (HIV), Hepatitis C Virus (HCV), and Hepatitis B Virus (HBV) were evaluated to determine their accuracy after storage at various temperatures/humidities. Rates of positive tests of control groups, experimental groups, and industry standards were compared (Fisher's exact chi2, p < or = 0.05). Compared to the control group, 2 of 10 HIV detection devices were adversely affected by exposure to high temperature/high humidity or high temperature/low humidity. With one exception, none of the environmentally exposed HCV or HBV detection devices exhibited significant differences compared to those stored under control conditions. For HIV, HCV, and HBV devices, there were differences compared to the industry standard. Collectively, this evaluation of pathogen detection kits revealed that diagnostic performance varies among products and storage conditions, and that the tested products cannot be considered to be approved for use to screen blood, plasma, cell, or tissue donors. [ABSTRACT FROM AUTHOR]

Rapid user-friendly ABO-Rh blood typing kits (Eldon Home Kit 2511, ABO-Rh Combination Blood Typing Experiment Kit) were evaluated to determine their accuracy when used under simulated military field conditions and after long-term storage at various temperatures and humidities. Rates of positive tests between control groups, experimental groups, and industry standards were measured and analyzed using the Fisher's exact chi-square method to identify significant differences (p < or = 0.05). When Eldon Home Kits 2511 were used in various operational conditions, the results were comparable to those obtained with the control group and with the industry standard. The performance of the ABO-Rh Combination Blood Typing Experiment Kit was adversely affected by prolonged storage in temperatures above 37 degrees C. The diagnostic performance of commercial blood typing kits varies according to product and environmental storage conditions. [ABSTRACT FROM AUTHOR]

To help preserve in-theater strength within deployed military units, commercially available, rapid, user-friendly ABO-Rh blood typing kits were evaluated to determine their stability in storage conditions commonly encountered by the warfighter. Methods for environmental exposure testing were based on MIL-STD-810F. When Eldon Home Kits 2511 were exposed to various temperature/relative humidity conditions, the results were comparable to those obtained with the control group and those obtained with industry-standard methods. For the ABO-Rh Combination Blood Typing Experiment Kits, 2 of the exposure treatments rendered them unusable. In addition, a third set of exposure treatments adversely affected the kits, resulting in approximately 30% blood type misclassifications. Collectively, this evaluation of commercial blood typing kits revealed that diagnostic performance can vary between products, lots, and environmental storage conditions. [ABSTRACT FROM AUTHOR]

The purpose of this study was to measure select properties of four temporary filling materials suitable for use in treating minor dental emergencies in the field. Specimens were made of each of the following four materials: intermediate restorative material, Fuji IX GP Fast, Ketac-Molar Quick, and the forward-deployable dental dressing recently developed by the Naval Institute for Dental and Biomedical Research. Twenty-fours hours after specimen fabrication, five properties (hardness, compressive strength, diametral tensile strength, flexural strength, and flexural modulus) were measured for each of the materials and compared using analysis of variance and Tukey-Kramer tests to determine whether significant differences existed among the materials (alpha = 0.05). Data analysis revealed that significant differences existed among the products for all of the properties tested. The forward-deployable dental dressing's properties compared favorable with and, in many cases exceeded those of intermediate restorative material, Fuji IX GP Fast, and Ketac-Molar Aplicap Quick. [ABSTRACT FROM AUTHOR]

Abstract: Objective: The purpose of this paper was to review the composition, properties, biocompatibility, and the clinical results involving the use of mineral trioxide aggregate (MTA) materials in endodontic treatment. Methods: Electronic search of scientific papers from January 1990 to August 2006 was accomplished using PubMed and Scopus search engines (search terms: MTA, GMTA, WMTA, mineral AND trioxide AND aggregate). Results: Selected exclusion criteria resulted in 156 citations from the scientific, peer-reviewed dental literature. MTA materials are derived from a Portland cement parent compound and have been demonstrated to be biocompatible endodontic repair materials, with its biocompatible nature strongly suggested by its ability to form hydroxyappatite when exposed to physiologic solutions. With some exceptions, MTA materials provide better microleakage protection than traditional endodontic repair materials using dye, fluid filtration, and bacterial penetration leakage models. In both animal and human studies, MTA materials have been shown to have excellent potential as pulp-capping and pulpotomy medicaments but studies with long-term follow-up are limited. Preliminary studies suggested a favorable MTA material use as apical and furcation restorative materials as well as medicaments for apexogenesis and apexification treatments; however, long-term clinical studies are needed in these areas. Conclusion: MTA materials have been shown to have a biocompatible nature and have excellent potential in endodontic use. MTA materials are a refined Portland cement material and the substitution of Portland cement for MTA products is presently discouraged. Existing human studies involving MTA materials are very promising, however, insufficient randomized, double-blind clinical studies of sufficient duration exist involving MTA for all of its clinical indications. Further clinical studies are needed in these areas. [Copyright &y& Elsevier]

The purpose of this work was to evaluate the clinical performance of a number of types of field (i.e., portable) dental equipment used under actual military deployment conditions. This equipment is often used under demanding field conditions where temperature, humidity, and air quality are not controlled. This article presents the results of a project conducted by the Naval Institute for Dental and Biomedical Research and the Air Force Dental Evaluation and Consultation Service to evaluate commercially available field dental equipment through laboratory testing and clinical user evaluations at military deployment sites. The purpose of the study was to identify the best-performing and most cost-effective field dental equipment for possible operational use by the U.S. Navy. Initial laboratory testing was performed at the Naval Institute for Dental and Biomedical Research and the equipment was then shipped to Okinawa, Japan, where it was tested by military dentists and assistants under deployment conditions. The testing provided beneficial results by identifying equipment that performed properly and equipment that exhibited shortcomings serious enough to render it inappropriate for field use. [ABSTRACT FROM AUTHOR]

Purpose: To determine the accuracy of commercially available, handheld light-emitting diode (LED) and halogen-based radiometers using LED and quartz-tungsten-halogen (QTH) curing lights with light guides of various diameters. Methods: The irradiance of an LED curing light (L.E.Demetron 1, SDS/Kerr, Orange, CA, USA) and a QTH curing light (Optilux 501, SDS/Kerr) were measured using multiple units of an LED (Demetron L.E.D. Radiometer, SDS/Kerr) and a halogen radiometer (Demetron 100, SDS/Kerr) and compared with each other and to a laboratory-grade power meter (control). Measurements were made using five light guides with distal light guide diameters of 4, 7, 8, 10, and 12.5 mm. For each light guide, five readings were made with each of three radiometers of each radiometer type. Data were analyzed with two-way analysis of variance/Tukey; α=0.05. Results: In general, both handheld radiometer types exhibited significantly different irradiance readings compared with the control meter. Additionally, readings between radiometer types were found to differ slightly, but were correlated. In general, the LED radiometer provided slightly lower irradiance readings than the halogen radiometer, irrespective of light source. With both types of handheld radiometers, the use of the larger-diameter light guides tended to overestimate the irradiance values as seen in the control, while smaller-diameter light guides tended to underestimate. CLINICAL SIGNIFICANCE The evaluated LED or halogen handheld radiometers may be used interchangeably to determine the irradiance of both LED and QTH visible-light-curing units. Measured differences between the two radiometer types were small and probably not clinically significant. However, the diameter of light guides may affect the accuracy of the radiometers, with larger-diameter light guides overestimating and smaller-diameter guides underestimating the irradiance value measured by the control instrument. [ABSTRACT FROM AUTHOR]

Dental officers and technicians must have reliable, durable, well-performing field dental equipment to enable them to provide dental care to deployed troops in operational environments. Unfortunately, no organized program exists to test such equipment before its purchase and use in the field. This article presents the results of a project conducted by the Naval Institute for Dental and Biomedical Research and the Air Force Dental Evaluation and Consultation Service to evaluate commercially available field dental equipment through laboratory testing and clinical-user evaluations in theater. The purpose of this 2-year project was to identify the best-performing and most cost-effective field dental equipment for possible future procurement. Initial laboratory testing was performed at the Naval Institute for Dental and Biomedical Research, and the equipment was then shipped to Kuwait for in-theater environmental and clinical-user testing. A seven-member scientific team of military dental officers and technicians was deployed for 1 month to perform in-theater testing under regional environmental conditions and to coordinate clinical-user evaluations. The testing provided beneficial results by identifying equipment that performed properly and equipment that exhibited shortcomings serious enough to render it inadequate for operational use. It is recommended that the project serve as a model for future testing and evaluation of medical/dental equipment by all of the military services. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the effect of a light-transmitting post on the depth of cure of a resin composite.Methods. Acetate resin molds were filled with resin composite in which a light-transmitting post was inserted into the center and photopolymerized to the manufacturer''s recommendations. Identical molds without a light-transmitting post were photopolymerized in a similar matter and served as a control. Molds were sectioned on a water-cooled, diamond saw at prescribed distances and the depth of cure was determined using a Knoop Hardness bottom-to-top ratio criterion. Data within each group were analyzed using 2-way (depth-by-distance) repeated measure ANOVA. Between-group contrasts (post versus no post) were accessed by a 3-way (2 within-subjects and 1 between-subjects) ANOVA with critical p=0.05.Results. The presence of the post did increase (p<0.001) Knoop Hardness values in simulated apical regions as compared to a control. However, there was no difference in the depth of cure between the groups (3-way analysis p=0.2) and also when evaluated using an 80% bottom-to-top Knoop Hardness ratio.Significance. The results suggest that these posts may have a limited utility when judged against a Knoop Hardness ratio criterion. [Copyright &y& Elsevier]