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Purpose: To evaluate whether reduced curing performance due to compromised light tip placement can be mitigated by bulk-fill composite and/or high-intensity curing light. Methods: Plastic discs with 2.5-mm deep cavities were filled with a conventional (Mosaic™) or bulk-fill (Tetric® PowerFill) composite and cured with a BluePhase® PowerCure curing light at normal and high-power settings, with light tip placement at distance and/or 45 degree angle. Curing time and irradiance were three, five, or 10 seconds at 1,200, 2,000, or 3,000 mW/cm2 (10 samples). After 24 hours, Vickers hardness on top and bottom surfaces was measured and analyzed using analysis of variance and pairwise comparisons (α<0.05). Results: All top surfaces had higher hardness than bottom surfaces. Cure (bottom-to-top hardness ratio) was significantly affected by material, distance/angle, and curing regimen (P<0.001), and generally decreased when tip distance and angle increased. Bottom-to-top hardness ratios of bulk-fill composite (0.42 to 0.66) were significantly higher than those of conventional composite (0.20 to 0.31). High-power curing significantly increased bulk-fill's curing performance as it was specifically formulated for this curing light. Conclusions: Increased light tip distance and angle compromised composite curing. Bulk-fill composite cured better at the bottom of the restoration than conventional composite regardless of light tip distance/angle. High-power light curing improved curing performance only in bulk-fill composite. Nevertheless, due to low bottom-to-top ratios (0.20 to 0.66) across all samples, even under ideal light tip placement, both composites should be cured in increments of less than 2.5 mm.

Per- and polyfluoroalkyl substances (PFAS) are refractory anthropogenic chemicals and current treatment processes at municipal water resource recovery facilities (WRRFs) cannot efficiently degrade them, hence, these chemicals cycle through the environment. Certain PFAS can be concentrated in biosolids from WRRFs and are commonly land applied for beneficial reuse. Given recent advances in measurement of PFAS, documentation of the range of concentrations in pre-stabilized sludge and stabilized biosolids is critical to evaluating treatment best practices and assessing potential human health and ecological risks. In this study, pre-stabilized sludge and post-stabilized biosolids samples were collected from 12 major WRRFs across the United States. PFAS were analyzed using Environmental Protection Agency (EPA) Method SW846-3500C/537.1, and Draft EPA Method 1633, by one commercial laboratory and two university research laboratories, respectively. Results comparison among laboratories demonstrated statistical differences in PFAS concentrations among split samples. For example, 5:3 FTCA (fluorotelomer carboxylic acid) concentrations in post-stabilized sludge at Lab 1 were measured at 21 ng/g (dry), while they were detected at 151 ng/g (dry) in Lab 3. Further, higher PFAS concentrations were observed in post-stabilized biosolids compared to pre-stabilized sludges, regardless of the laboratory or analysis method, even when solids destruction through solids stabilization was considered. Further research is required to refine methods for analyses of PFAS in sludge and biosolids samples from WRRFs prior to being used for development of regulatory actions as well as understanding how various treatment protocols could impact concentrations of PFAS in land-applied biosolids., (© 2024 The Author(s). Journal of Environmental Quality published by Wiley Periodicals LLC on behalf of American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.)

Purpose: The purpose of this study was to investigate the microleakage of atraumatic glass ionomer restorations with and without silver diammine fluoride (SDF) application. Restorations with SDF are termed silver-modified atraumatic restorations (SMART). Methods: Sixty carious extracted permanent teeth were randomly allocated to two SMART groups and two control groups (n equals 15 per group) for a total of four groups. After selective caries removal, test specimens were treated with 38 percent SDF and polyacrylic acid conditioner was applied and rinsed; teeth were restored with Fuji IX GP® glass ionomer (n equals 15) or with SMART Advantage™ glass ionomer (SAGI; n equals 15). For control groups, specimens were restored with their respective GI material after selective caries removal, both without SDF. Restored teeth were placed in Dulbecco's Phosphate-Buffered Saline solution at 37 degrees Celsius for 24 hours. Teeth were thermocycled between five and 55 degrees Celsius for 1,000 cycles, stained with two percent basic fuchsin, sectioned, and visually inspected for microleakage utilizing stereomicroscopy on a four-point scale. Data were statistically analyzed using Kruskal-Wallis one-way analysis of variance on ranks using Dunn's method (P<0.05). Results: Microleakage between the two SMART restoration groups was insignificant. SAGI alone demonstrated significantly more microleakage than all other groups. There was no statistical significance between the Fuji IX GP® control group and the two SMART restoration groups. Conclusions: This in vitro study indicated that silver diammine fluoride placed before glass ionomer restoration does not increase microleakage. Polyacrylic acid may be used after SDF placement without increasing microleakage.

Per- and polyfluoroalkyl substances (PFAS) are a recalcitrant group of chemicals and can be found throughout the environment. They often collect in wastewater systems with virtually no degradation prior to environmental discharge. Some PFAS partitions to solids captured in wastewater treatment which require further processing. Of all the commonly applied solids treatment technologies, incineration offers the only possibility to completely destroy PFAS. Little is known about the fate of PFAS through incineration, in particular, for the systems employed in water resource recovery facilities (WRRF). This review covers available research on the fate of PFAS through incineration systems with a focus on sewage sludge incinerators. This research indicates that at least some PFAS destruction will occur with incineration approaches used at WRRFs. Furthermore, PFAS in flue gas, ash, or water streams used for incinerator pollution control may be undetectable. Future research involving full-scale fate studies will provide insight on the efficacy of PFAS destruction through incineration and whether other compounds of concern are generated. PRACTITIONER POINTS: Thermal processing is the only commercial approach available to destroy PFAS. Thermal degradation conditions required for destruction of PFAS during incineration processes are discussed. Fate of PFAS through water resource recovery facility incineration technologies remains unclear. Other thermal technologies such as smoldering combustion, pyrolysis, gasification, and hydrothermal liquefaction provide promise but are in developmental phases., (© 2020 Water Environment Federation.)

Pediatric dentistry has evolved. Seasoned pediatric dentists believe that patients, parents, and behavior techniques have changed over their practice lifetimes. The purpose of this article is to provide dentists with a framework in which to adapt to the changes in society. Understanding cultural diversity, current societal values, technology and media influences, and contemporary parenting philosophies is essential to fostering communication with patients and their families. Building and honing behavior guidance skills are part of the process by which dentists help turn child patients into fearless adult patients with excellent oral health. This article reviews basic techniques and offers practical examples of implementing these in daily practice. The discussion also addresses changing parental and societal acceptance of various techniques and dentists' responsibility for informed consent regarding the risks and benefits of advanced behavior guidance techniques. Treating a patient from childhood to adulthood is the ultimate opportunity for the dentist to play a vital role in advancing the health and wellness of another human being.

Purpose: To investigate intrapulpal temperature rise in a primary molar during light activation of a composite restoration to determine if clinically significant pulpal temperatures (greater than 5.5 degrees Celsius) were reached., Methods: Restorative composites (EsthetX HD, Filtek Supreme Ultra, Filtek Bulk Fill) were placed into a primary molar with occlusal preparation (1.5 mm depth; remaining pulpal floor thickness one mm). The pulp was extirpated through a root access to place a thermocouple against the pulpal roof. Temperature changes were recorded during composite restoration light polymerization with three curing lights (one quartz-tungsten-halogen, two LEDs). Sample size was 10. Samples received additional irradiation to assure complete polymerization, followed by a third irradiation for calculating the exothermic heat contribution (subtracting third irradiation temperatures from first irradiation temperatures). Cured restorations were removed after each test, and the tooth was reused. Results were analyzed with Kruskal-Wallis (α =0.05)., Results: Type of curing light and composite material affected the intrapulpal temperature rise, which was up to five degrees Celsius for one combination of LED-composite., Conclusions: Clinicians should be aware of the potential for clinically significant intrapulpal temperature rises when light-activating composite restorations in a primary molar with a moderately deep cavity.

Objective: To determine whether recommended short curing times of three high-power light emitting diode (LED) curing lights are sufficient to polymerize sealant materials., Methods: Opaque-unfilled sealant (Delton LC Opaque), opaque-filled sealant (UltraSeal XT plus), and clear-filled sealant (FluroShield) were light cured in a covered slot-mold using the manufacturers' shortest recommended curing times with three high-power LED lights (3-s VALO, 5-s Fusion, 10-s Smartlite). A 40-s cure with a quartz-tungsten halogen (QTH) light was used as control. Vickers hardness was measured 24 h after curing at the sealant surface and through the depth (0.5 mm increments) (N = 10). Results were analyzed with two-way anova (pair-wise multiple comparisons, significance level 0.05)., Results: The high-power LEDs did not cure the sealants as deep as the QTH. Delton LC Opaque showed the least depth of cure as hardness values beyond a depth of 0.5 mm were not measurable regardless of the curing light. Even for UltraSeal XT plus, when surface hardness was about the same with all lights, hardness decreased more rapidly with depth for the LEDs. FluroShield showed the slowest decline in hardness through the depth for all lights., Conclusions: Manufacturers' recommendations for shortest possible curing time with high-power LEDs were not sufficient for adequate polymerization of the tested sealants., (© 2014 BSPD, IAPD and John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Sorption characteristics of eight drugs related to recreational and clandestine activity-amphetamine, cocaine, heroin, N-formyl amphetamine, N-formyl methamphetamine, methamphetamine, 3, 4-methylenedioxymethamphetamine (MDMA), and pseudoephedrine-were evaluated on selected kitchen countertop surfaces. Methanol-dampened Whatman 40 filter paper wipes were used to collect samples from eleven surfaces including alkyd resin, ceramic tiles, glass, granite, laminate, limestone, marble, quartz compac, quartz real, soap stone, and stainless steel. The filter paper wipes were analyzed by a rapid three-minute UPLC-QTOF method, following ammonium acetate buffer (pH 5.8-6.2) extraction. The average percentage recoveries after 15 h of exposure to the surface materials tested, was found to be highest for cocaine and MDMA and lowest for amphetamine and methamphetamine. Among the eleven countertop surfaces, overall recoveries for marble were observed to be the least, whereas soapstone, quartz compac and stainless steel were among the highest. Scanning electron microscopic images of the surfaces provided a unique view of surface irregularities that potentially influenced drug recovery. Aging, migration, solvent composition, and volatility were examined. The variation in recovery of drugs was attributed to four key factors: compound volatility, surface composition, surface-compound interaction, and solvent composition., (Copyright © 2013 Elsevier B.V. All rights reserved.)

As a key component of the craniofacial team in caring for children with craniofacial anomalies, pediatric dentists play a vital role in the treatment and prevention of dental disease. The purpose of this paper was to review the current literature on the oral health status of individuals with craniofacial anomalies, concentrating on children with cleft lip and/or palate (CLP). CLP children are at high risk for developing caries and periodontal disease, have poor oral hygiene, and often have unmet dental needs. Recommendations for pediatric dentists caring for children with craniofacial anomalies include providing parent education, dietary counseling, oral hygiene instructions for the parent and child and implementing other preventive measures.

The identification and quantitation of the non-ecstasy amphetamine-type stimulants (ATSs) amphetamine and methamphetamine in lakes, rivers, wastewater treatment plant influents, effluents, and biosolids are reviewed. Neither monitoring nor reporting is required of these ATSs, which are considered emerging pollutants, but they have been identified in the environment. Amphetamine and methamphetamine enter our water supply by human excretion after legal or illegal consumption and via manufacturing in clandestine laboratories. Analytical methodology for sampling, sample preparation, separation, and detection of ATSs is discussed. Reported occurrences of ATSs in the environment and their use in municipal sewage epidemiology are noted. Future research needs that challenge applications of analytical techniques are discussed. The review focuses on research reported from 2004 to 2009., (Copyright 2010 Elsevier B.V. All rights reserved.)

Environmentally contaminated aqueous samples are examined for evidence of stereoselective degradation of metolachlor. The unique chemical structure of metolachlor, a chloroacetamide herbicide, consists of four stereoisomers due to axial and/or C-chirality. The degradation of metolachlor is monitored over time in agricultural runoff water that is applied to a subsurface flow constructed wetland. Metolachlor stereoisomers are isolated from aqueous samples by achiral reversed-phase solid-phase extraction and analyzed by normal-phase high-performance liquid chromatography using a chiral stationary phase. The analyses of 64 post-application samples, collected over a period of four weeks, are reported. The samples are filtered (0.45 microm) prior to analysis and thereby represent metolachlor in solution and/or associated with dissolved organic carbon. Sixteen samples demonstrate total racemic metolachlor concentrations greater than 10 ppb. Of these 16 samples, one sample is determined statistically to demonstrate enantioselective degradation. Significant contributions made by this study include the evaluation of stereoselectivity based on mathematically derived fractions, rather than ratios, and statistical evaluation of precision establishing the variability resulting from chromatographic processes versus metabolic processes. The research demonstrates that distribution of metolachlor between the solid phase composed of chemical and/or biological particulates and the aqueous phase is not primarily stereoselective, and that stereoselectively enriched metolachlor does not dominate in the aqueous phase.

The significance of this research is that it improves analytical methodology used for organic chemicals in aqueous solutions by establishing the feasibility of heterogeneous chemical derivatization at the liquid-solid interface (i.e., solid-phase reaction or solid-phase derivatization). A solid-phase derivatization method for determining chlorinated herbicide acids was developed. Solid-phase extraction was used to concentrate and retain analytes on sorbents for subsequent solid-phase derivatization. Background interferences were removed from the chromatograms by electronically subtracting the responses of blank, nonfortified analyses from spiked samples. Two extraction sorbents (octadecyl bonded silica and polystyrene-divinylbenzene) and two derivatizing reagents (BF3-MeOH and trimethylsilyldiazomethane) were investigated. Recovery of 13 chlorinated herbicide acids--including pentachlorophenol, dinoseb, and bentazon (having a derivatizable functional group, -OH or -NH, bonded directly to a phenyl group); dicamba, picloram, acifluorfen, 3,5-dichlorobenzoic acid, and dacthal (having a derivatizable functional group, -COOH, bonded directly to a phenyl group); and 2,4-D, 2,4,5-T, dichlorprop, 2,4,5-TP, and 2,4-DB (having a derivatizable functional group, -COOH, bonded directly to a sp3 carbon atom)--was tested. The analytical method developed was proven successful for determining acidic herbicides, except for the dacthal diacid metabolite, in aqueous samples.

The significance of this research is the application of thin-layer chromatography (TLC) to fractionate well-characterized aquatic humic materials coupled with the novel evaluation of the trihalomethane formation potential (THMFP) of the fractionated materials. Disinfection by-products such as trihalomethanes (THMs) form when natural water is treated by chlorination. Nordic Aquatic and Suwannee River fulvic and humic acids, obtained from the International Humic Substances Society, were prepared at pH 6 and 9 and fractionated on silica gel plates using a mobile phase consisting of methanol and ethyl acetate (2:1, v:v). Based on retention factor (R(f)) values, three common fractions were identified in all substances examined. Additionally, other fractions were noted that were characteristic of specific humic substances. Each of the three primary fractions derived from Nordic Aquatic fulvic acid at pH 6 demonstrated the potential to contribute to formation of THMs. This research provides data to support the hypothesis that differences in the chemical structure and composition of natural organic matter (NOM) significantly affect the potential to react with chlorine to form THMs.

Analyses of fatty acid (FA) composition in freshwater fishes promote understanding of the potential relationship between fish health or human nutrition and specific FAs. Therefore, the chemical identity of FAs in endemic fishes must be established. Paddlefish, sauger, and white bass were collected from the Ohio River. The structural identification of esterified FAs from fish-fillet lipids was conducted using gas chromatography-mass spectrometry (GC-MS). The same 13 FAs, composing more than 90% of the mass of FAs extracted by techniques used in this research, were found in all three species examined. Carbon chain length and degree and position of unsaturation were determined from the characteristic ionization and fragmentation of FA methyl esters (FAMEs) resulting from GC-MS electron impact (EI) and chemical ionization (CI) modes. Assignment of structure to the extracted FAs required complementary interpretation of both EI and CI MS. The EI spectra observed substantiate findings reported in the literature. The novelty of this research is in the thorough interpretation of CI spectra for which less data are available. The observations reported for analyses of fishes will be useful to all researchers studying FAs regardless of sample media.

The transport and fate of pesticides applied to ornamental plant nursery crops are not well documented. Methodology for analysis of soil and water runoff samples concomitantly containing the herbicides simazine (1-chloro-4,6-bis(ethylamino)-s-triazine) and 2,4-D ((2,4-dichlorophenoxy)acetic acid) was developed in this research to investigate the potential for runoff and leaching from ornamental nursery plots. Solid-phase extraction was used prior to analysis by gas chromatography and liquid chromatography. Chromatographic results were compared with determination by enzyme-linked immunoassay analysis. The significant analytical contributions of this research include (1) the development of a scheme using chromatographic mode sequencing for the fractionation of simazine and 2,4-D, (2) optimization of the homogeneous derivatization of 2,4-D using the methylating agent boron trifluoride in methanol as an alternative to in situ generation of diazomethane, and (3) the practical application of these techniques to field samples.