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Mohammed S Aldossary,1 Eman H Ismail,2 Mashael M Almutawaa,3 Shahad M Alhajri,1 Afnan M Almuaddi,1 Mervat M El Dalatony1,4 1General Directorate of Research and Studies, Ministry of Health, Riyadh, Saudi Arabia; 2Clinical Dental Science Department, College of Dentistry, Princess Nourah bint Abdulrahman University, Riyadh, Saudi Arabia; 3Department of Prosthodontics, College of Dentistry and Nursing, Vision Colleges, Riyadh, Saudi Arabia; 4Public Health & Community Medicine Department, Faculty of Medicine, Menoufia University, Shibin El Kom, Menoufia Governorate, EgyptCorrespondence: Eman H Ismail, Clinical Science Department, College of Dentistry, Princess Nourah bint Abdulrahman University, Airport Road, Riyadh, Saudi Arabia, Email ismail.e.h@hotmail.com; ehismail@pnu.edu.saPurpose: Understanding the factors that influence the level of patient satisfaction with dental services and identifying the strengths and weaknesses in dental clinics will subsequently increase patient satisfaction and contribute to improving dental care quality. This study aims to evaluate the variables that impact patients’ satisfaction with dental services received in specialized dental care centers of the Ministry of Health in Saudi Arabia.Patients and Methods: Secondary data at the national level from a patient experience program were used in this study. Completed Press Ganey® surveys submitted by patients during the first half of 2022 were included. The effect of the different domains (access to dental clinic, moving through dental visit and dentist) on the overall assessment rating of patient satisfaction was assessed using Pearson’s correlation coefficient (r) and multiple linear regression models.Results: A total of 964 surveys were completed and subsequently analyzed. The overall assessment rate of patient satisfaction was 73.4%. All items of the domains showed highly significant correlation levels (P < 0.001). However, the Dentist domain exhibited the highest correlation with the overall assessment rate of ‎patient satisfaction.Conclusion: The dentist acts as the most significant predictor of patient satisfaction.Keywords: patient satisfaction, patient-centered care, quality of health care, Saudi Arabia

During embryonic development and adult life, brain cavities and ventricles are filled with cerebrospinal fluid (CSF). CSF has attracted interest as an active signaling medium that regulates brain development, homeostasis and disease. CSF is a complex protein-rich fluid containing growth factors and signaling molecules that regulate multiple cell functions in the central nervous system (CNS). The composition and substance concentrations of CSF are tightly controlled. In recent years, it has been demonstrated that embryonic CSF (eCSF) has a key function as a fluid pathway for delivering diffusible signals to the developing brain, thus contributing to the proliferation, differentiation and survival of neural progenitor cells, and to the expansion and patterning of the brain. From fetal stages through to adult life, CSF is primarily produced by the choroid plexus. The development and functional activities of the choroid plexus and other blood–brain barrier (BBB) systems in adults and fetuses have been extensively analyzed. However, eCSF production and control of its homeostasis in embryos, from the closure of the anterior neuropore when the brain cavities become physiologically sealed, to the formation of the functional fetal choroid plexus, has not been studied in as much depth and remains open to debate. This review brings together the existing literature, some of which is based on experiments conducted by our research group, concerning the formation and function of a temporary embryonic blood–CSF barrier in the context of the crucial roles played by the molecules in eCSF.

Objective: This study evaluated the completeness and accuracy of information in LCU instruction manuals from 40 manufacturers., Materials and Methods: Instruction manuals from 40 LCUs (20 from leading manufacturers and 20 budget units) were reviewed. Twenty-eight parameters across five categories were assessed using a binary scale (0=incorrect/missing, 1=correct). The categories and their respective evaluation scores were: LCU characteristics (43%), instructions for use (7%), safety precautions (14%), maintenance recommendations (29%), and regulatory certification (7%). These scores were combined to produce a final score., Results: Scores from leading manufacturers ranged between 46-86%, while the budget category ranged from 18-68%. All manuals provided information about the wavelength/spectrum of the LCU. Only Valo X and Valo Cordless reported power values and used the term "irradiance" instead of "intensity." Details such as LED type and active tip emission area were often missing. Instructions on how to use the LCU to photo-cure resins were frequently limited. Although most manuals addressed safety precautions, several lacked details on heat issues and general health precautions. All manuals included maintenance instructions, though information on replacement parts was often missing. Among the LCUs, 85% stated they were CE certified, 32% held both FDA and CE certification, and 63% claimed compliance with ISO and/or IEC standards., Conclusions: There were notable differences in the completeness and accuracy of the instruction manuals. Manuals from major manufacturers generally provided more comprehensive information than their budget counterparts., Clinical Significance: Instruction manuals should contain accurate information to help clinicians deliver the highest standard of care. The lack of important information about the LCUs in the manuals is concerning., (© 2024 Wiley Periodicals LLC.)

A reliable solid-liquid extraction protocol coupled with liquid chromatography-electrospray ionization-tandem mass spectrometry in the negative-ion mode was developed and validated for illegal bromate determination in preliminary and bakery products. Crude and dried-treated samples were directly extracted with acetonitrile-water (4:1, v/v). Bromate was determined using a Phenomenex Synergi™ Polar reversed-phase column and MS/MS under multiple reaction monitoring. The chosen solvent efficiently extracted bromate with all applied extraction-assisting techniques (p > 0.05). Although this assay avoids cleanup procedures, matrix effect of <-11% was achieved. Rapid bromate separation in only 8 min was attained by a reversed-phase column. In both commodities, linearity range, R 2 , recovery%, repeatability, intermediate precision, LOD and LOQ results were 0.05-100 ng mL -1 , >0.9999, 88.6-103%, 2.93-9.80% and 9.64-10.10%, 0.015 μg kg -1 and 0.05 μg kg -1 , respectively. Out of 288 tested real samples, 13.9% of violations were observed. This high-sensitivity protocol offers effective oversight and consumer protection., Competing Interests: Declaration of competing interest The authors declare that they are not aware of any financial or interpersonal issues that might have appeared to have an impact on the study that was the subject of this work., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Purpose: Secondary caries around ceramic restorations is the most common reason for the replacement of fixed dental prostheses (FDPs). Therefore, it is important to examine the susceptibility of different ceramic materials to biofilm formation. This study aimed to evaluate biofilm development and associated roughness and color alterations in three lithium disilicate ceramics: Emax CAD (EC), Emax Press (EP), and LiSi Press (LP)., Materials and Methods: Streptococcus mutans biofilms were grown on the three ceramics (n = 10 per group) for 7 days. Surface roughness values and color alteration were assessed before and after the biofilm using a non-contact profilometer and spectrophotometer, respectively. Biofilm growth was evaluated using colony-forming units (CFUs) and scanning electron microscope (SEM) images. The data were analyzed using one-way ANOVA and Tukey tests., Results: There was a significant (p ≤ 0.001) growth of S. mutans colonies on EC (6.75 ± 0.56) and EP (6.72 ± 0.54) specimens compared to LP, which showed no biofilm growth. The change in average surface roughness (∆R a , nm) was significantly lower (p < 0.001) in the EC specimens (0.029 ± 0.003) compared to the EP (0.055 ± 0.012) and LP (0.041 ± 0.010). When the changes in the R v and R t values were investigated, no significant difference was observed among the groups. Following the biofilm challenge, the change in color (∆E 00 ) was significantly lower (p = 0.005) in the LP group (1.68 ± 1.45) compared to the EC group (3.89 ± 1.50) and no significant difference was observed between the EP group (2.74 ± 1.01) and the other two ceramics (p ≥ 0.05)., Conclusion: LP ceramics exhibited superior resistance to S. mutans biofilm formation and associated changes in surface roughness and color compared to the Emax CAD and Emax Press ceramics. These findings suggest that the LiSi Press material may be more favorable to mitigate the risk of secondary caries., (© 2024 by the American College of Prosthodontists.)

The deep margin elevation (DME) technique has gained popularity because of numerous supporting case reports. However, some clinicians are cautious regarding using this technique owing to the lack of clear case selection criteria for DME application. This review aimed to analyze case reports and a series of DME cases to determine pre-/post-operative evaluation methods that could be used to suggest a pre-operative case selection checklist for DME. An electronic database search was conducted in June 2021 and updated by June 2023 using selected terms from PubMed, Cochrane Library, Google Scholar, EBSCO, and Scopus. The search was limited to English-language publications and was not restricted to the date. The inclusion criteria were case reports/series addressing periodontal and restorative outcomes of DME. The search identified 217 articles, 76 of which were pertinent. However, only six case reports and one case series satisfied the inclusion criteria. None of the selected studies followed any reporting guidelines, which led to significant information gaps. While the reviewed studies reported favorable outcomes, standardized protocols for evaluating pre-/post-operative restorative and periodontal status were lacking. The post-operative follow-up period varied from 3 months to 6 years. Designing and implementing pre-/post-operative guidelines hold the potential for ensuring the safe application of the DME technique. This may enhance our understanding of the suitability and efficacy of such non-invasive technique in future clinical trials., Clinical Significance: Handling deep cavities and preparing crowns are challenging. However, a lack of understanding of when to perform DME can lead to missed opportunities for conservative treatment, thereby a disservice to the patient. Provision of safe guidelines should be employed by clinicians until further evidence either supports or contradicts this treatment method., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 THE AUTHORS.)

Background: Proper light curing is crucial for the success of restorative dentistry and to bond brackets to teeth, yet the responsibility is often delegated to dental assistants (DAs). This study assessed the proficiency and maintenance protocols of DAs when using light-curing units (LCUs) in Saudi Arabia., Methods: Self-administered questionnaires were distributed to practicing DAs. The questionnaire contained sections on knowledge, adherence to best practices, and how to maintain the LCU. Demographic data were collected as well. Descriptive statistics and linear regressions at a significance level of (p = 0.05) were conducted to identify any relationships that influenced the DAs' LCU knowledge, practice, and maintenance protocols., Results: Among the surveyed DAs, 66% were responsible for using the LCU during treatment, 16% used their fingers for support when light curing, 50% held the LCU tip 1-2 mm from the restoration during curing, and 51% did not have a specific maintenance protocol at their workplace. 70% did not know the output from the LCU, and their educational background correlated with knowledge (b = -14.42, p < 0.001). The type of institution type correlated with adherence to best practices (b = -13.65, p = 0.011), and level of knowledge and adherence to maintenance protocols showed a direct correlation (b = 0.002, p = 0.041)., Conclusions: The findings revealed that a significant percentage of the DAs who replied had insufficient knowledge and did not follow the best practices and maintenance protocols for the LCUs they were using. Their educational background and workplace factors influenced this knowledge gap, while the absence of a maintenance protocol and suboptimal practices were associated with the type of institution., Clinical Significance: To maintain the best practice, clinicians and institutions should improve the education and training of DAs. Otherwise, inadequate light curing by the DAs may jeopardize the long-term success of many dental procedures., (© 2023 Wiley Periodicals LLC.)

This study explores the effect of using dental brushes with or without metacrylate-based modeling resins on long-term color stability and surface topographies of resin-based composites. This study examined the effects of two variables: (1) the type of brush used (Art brush, Micro-brush, or Mylar strip) and (2) the application of a modeling resin (applied or not applied). The specimens were artificially aged through 10,000 cycles of thermocycling and subsequently immersed in coffee for 30 days. Measurements of color and surface roughness were taken at baseline and after the aging, using a non-contact profilometer for surface roughness and a spectrophotometer for color. Data were analyzed using paired t-tests and one-way ANOVA. Resin-based composites smoothed with dental brushes or micro brushes without modeling resins exhibited lower color change (ΔE) than other groups. Paired t-tests revealed significant differences in average surface roughness (Ra) and valley depth (Rv) for each surfacing technique before and after aging ( p  ⩽ 0.01). The root means square average of the profile heights (Rq) significantly increased in the control and micro-brush groups ( p  ⩽ 0.01). In conclusion, the use of brushes in resin-based composites placement does not increase the susceptibility to staining. Instead, the inclusion of resin modeling contributes to discoloration over time., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Objectives: The aim was to compare the porosity of different bulk-fill resin-based composites (RBCs) placement techniques to the conventional incremental technique using microcomputed tomography (μ-CT)., Material and Methods: Occlusal cavities were prepared on extracted human molars, divided into five groups based on the placement technique (n = 10/group). Techniques examined were Monoblock-two-step (SureFil SDR flow + Ceram.X), Monoblock-two-step (Tetric EvoFlow Bulk-Fill + Tetric EvoCeram Bulk-Fill), Monoblock-one-step (Tetric EvoCeram Bulk-Fill), Monoblock with sonic activation (SonicFill2), and incremental technique (Filtek Z250). μ-CT scanning (SkyScan, Bruker, Belgium) assessed the number, volume of closed pores, and total porosity. Analysis of variance on ranks was used (Student-Newman-Keuls method and Mann-Whitney rank-sum test), to determine the significance of RBC viscosity and the sonication placement technique. The Spearman correlation method assessed the correlation between porosity characteristics (α = 0.05)., Results: The SonicFill2 presented a higher number of closed pores than the other groups (p < 0.05). The overall porosity within the restoration seemed greater in this order: Filtek Z250 > SonicFill2 > Tetric EvoFlow Bulk-Fill + Tetric EvoCeram Bulk-Fill > Tetric EvoCeram Bulk-Fill > SureFil SDR Flow + Ceram.X. Sonication was associated with increased number (p = 0.005) and volume (p = 0.036) of closed pores. A strong correlation was observed between the number and volume of closed pores (R 2  = 0.549, p < 001)., Conclusions: The monoblock technique with sonic activation showed significantly more internal porosity than the other placement techniques. Sonication during application contributed to the higher number and volume of closed pores than the passive bulk-fill application., Clinical Relevance: Using bulk-fill materials enhances efficiency, yet void formation remains an issue, depending on viscosity and active/passive delivery of materials. Clinicians must familiarize themselves with effective placement techniques to reduce void formation and optimizing treatment outcomes., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Effective communication among members of the dental team is essential for the delivery of high-quality dental care. However, an in-depth understanding of issues concerning the interrelationship between dental clinicians and laboratory technicians has not been previously undertaken. Therefore, the aim of the study was to explore factors influencing the interrelationship between dental clinicians and laboratory technicians., Methods: Semi-structured interviews were conducted with dental clinicians and laboratory technicians using purposeful snowball sampling. Two trained researchers conducted the interviews based on a pre-piloted topic guide. The interviews were conducted via video conferencing platform, audio-recorded, and transcribed verbatim. Field notes were taken during the interviews. Framework Methodology was used to analyze the data., Results: A total of 20 dental clinicians and laboratory technicians were interviewed. The average interview duration was 37 min. Participants mainly reported negative encounters and highlighted the importance of training and exposure, collaborative learning, and alignment of expectations of both parties in terms of cost of laboratory work, turnaround time, and patient preferences. The relationship between dental clinicians and laboratory technicians depends largely on effective teamwork dynamics and open communication channels. Increased workload, workforce shortage, availability of digital systems, management policies, and financial challenges were emphasized as organizational factors affecting the interrelationship between both groups. Participants highlighted the importance of shadowing, mentorship, education courses, joint discussions, patient-technician rapport, and adoption of digital technology for fostering collaborative practices between the professions., Conclusions: A multitude of factors influencing the dental clinician-laboratory interrelationship at individual, interpersonal and organizational levels were identified. This study highlights the need to build a transformative relationship underpinned by mutual trust and respect. Such a collaborative relationship will facilitate optimal patient care and successful treatment outcomes. The outcome of this study can help stakeholders identify solutions for enhancing the interrelationship among the dental team, to ultimately improve patient care and efficiency of dental services., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Purpose: This secondary analysis further analyzed variations in the 50:50% perceptibility and acceptability thresholds (PT and AT, respectively) pertaining to light, medium, and dark tooth-colored specimen sets., Methods: Primary raw data from the original study was retrieved. Visual thresholds (Perceptibility - PT and Acceptability - AT) were analyzed among the three specimen sets - light, medium, and dark. The Wilcoxon signed-rank test was used for paired specimens, and the Wilcoxon rank-sum nonparametric test was used for independent specimens (α= 0.001)., Results: The 50:50% CIEDE2000 PT and AT values were significantly higher for the light-colored specimen set when compared with the medium and dark-colored specimens: 1.2, 0.7, 0.6, respectively (PT) and 2.2, 16, 14 (AT), respectively (P< 0.001). Independent of the observer group, the highest PT and AT values were always found for the light-colored specimen sets (P< 0.001). Dental laboratory technicians had the lowest visual thresholds, but not significantly different from the other observer groups studied (P> 0.001). Similarly, all research sites had statistically higher visual thresholds for the light-colored specimen set than for the medium- or dark-colored sets, except for two sites that showed statistically similar results for medium-colored specimens but were significantly different from the dark-colored set. Among the different research sites, sites 2 and 5 registered significantly higher PT thresholds for the light specimens (1.5 and 1.6, respectively), and site number 1 had a significantly higher AT threshold relative to the other sites. The 50:50% perceptibility and acceptability thresholds were significantly different among light-, medium-, and dark-colored specimens for different research sites and observer groups., Clinical Significance: The visual perception of color difference related to light-, medium-, and dark-colored specimens varied based on observer group and their geographic location. Therefore, a greater understanding of factors that affect visual thresholds, with the observers being "the most forgiving" for color differences among the light shades, will allow diverse clinicians to overcome some of the challenges of clinical color matching., Competing Interests: The authors declared no conflict of interest., (Copyright©American Journal of Dentistry.)

The catalytic conversion of waste cooking oil (WCO) was carried out over a synthetic nano catalyst of cobalt aluminate (CoAl 2 O 4 ) to produce biofuel range fractions. A precipitation method was used to create a nanoparticle catalyst, which was then examined using field-emission scanning electron microscopy, X-ray diffraction, energy dispersive X-ray, nitrogen adsorption measurements, high-resolution transmission electron Microscopy (HRTEM), infrared spectroscopy, while a gas chromatography-mass spectrometer (GC-MS) was used to analyze the chemical construction of the liquid biofuel. A range of experimental temperatures was looked at including 350, 375, 400, 425, and 450 °C; hydrogen pressure of 50, 2.5, and 5.0 MPa; and liquid hour space velocity (LHSV) of 1, 2.5, and 5 h -1 . As temperature, pressure, and liquid hourly space velocity increased, the amount of bio-jet and biodiesel fractional products decreased, while liquid light fraction hydrocarbons increased. 93% optimum conversion of waste cooking oil over CoAl 2 O 4 nano-particles was achieved at 400 °C, 50 bar, and 1 h -1 (LHSV) as 20% yield of bio-jet range,16% gasoline, and 53% biodiesel. According to the product analysis, catalytic hydrocracking of WCO resulted in fuels with chemical and physical characteristics that were on par with those required for fuels derived from petroleum. The study's findings demonstrated the nano cobalt aluminate catalyst's high performance in a catalytic cracking process, which resulted in a WCO to biofuel conversion ratio that was greater than 90%. In this study, we looked at cobalt aluminate nanoparticles as a less complex and expensive alternative to traditional zeolite catalysts for the catalytic cracking process used to produce biofuel and thus can be manufactured locally, which saves the cost of imports for us as a developing country., (© 2023. The Author(s).)

The widespread use of chlorine pre-oxidation in water purification has been limited in several countries owing to the production of carcinogenic byproducts when combined with naturally occurring organic matter. This study investigates the efficient use of potassium permanganate (KMnO 4 ) pretreatment and coagulation enhancement as particle size and molecular weight distribution controlling parameters. KMnO 4 pretreatment significantly reduced the apparent molecular weight of humic acid due to KMnO 4 reduction and the continuous generation of manganese dioxide (MnO 2 ) formed in situ under neutral and alkaline conditions. The MnO 2 formed in situ had adsorption characteristics that enabled it to form large and stable flocs with the hydrolysis products of aluminum sulfate. However, under acidic conditions, KMnO 4 pretreatment exhibited strong oxidation characteristics due to Mn(VII) reduction to Mn(II), and the mean particle floc size was the same as without KMnO 4 pretreatment. Overall, KMnO 4 pretreatment is a useful alternative strategy for traditional pre-oxidation using chlorine and a good coagulant enhancement agent in neutral and basic media.

The current work investigated the preparation of Nano-particles of Co/Zn Al 2 O 4 as a catalyst via co-precipitation method. Several analyses, including BET, XRD, HRTEM, EDX, SEM, and FTIR, were used to characterize it. The analysis revealed that the prepared catalyst had an average surface area of 69.20 m 2 /g, a cross-sectional area of 16.2 m 2 /molecule, an average particle size of approximately 28 nm, and a pore size of 0.22 cm 3 /g. The prepared catalyst was used in a bio fuel synthesis process via thermo-catalytic cracking of waste cooking oil (WCO) in a single step batch reactor. Catalyst loading was tested with different weight percentage of 1.5%, 2%, and 2.5%. The pilot study revealed that the best conditions for optimizing bio jet fuel yield were 400 °C, a catalyst loading of 2%, and a reaction time of 30 min.The optimal cut-off from the distillation process of crude liquid bio fuel product which represents a fraction of bio-jet fuel was in the range from 150 to 240 °C., (© 2022. The Author(s).)

Objective: The objective was to provide a comprehensive overview of color interactions between resin composite (RC) and its surroundings, analyze the design and results of respective research studies, and provide clinical and research recommendations., Overview: Resin composite (RC) materials can adjust their color to that of surrounding enamel and dentin to a different extent. This phenomenon has been referred to as the "chameleon effect" in dental jargon, while color blending/adjustment/shifting/assimilation is more scientific terms. Studies that evaluated the color adjustment potential of RCs have employed different methods. This article discusses the (a) terminology used to describe color adjustment potential, (b) color science theories associated with color adjustment, (c) design of respective studies, including methods, specimens, and calculations, and (d) their outcome and reported results. Clinical implications and future directions related to the color adjustment potential of RCs are also provided., Conclusions: Factors that influence the color adjustment potential of RCs are classified into three categories: (1) material type, (2) cavity design, and (3) the substrate surrounding the restoration. Each factor can be optimized to enhance color matching and the restorative outcome., Clinical Significance: A material that blends well and exhibits pronounced color adjustment potential would likely improve the color match and therefore the esthetic outcome. These materials "work" for dental professionals by compensating for their suboptimal shade matching and/or lack of an excellent match in the used material. This review aims to further the understanding of the inherent properties of RCs and allow clinicians to fully utilize them to place RC restorations and minimize the time spent on modifying or replacing existing ones. Hence, the outcomes would encompass the increased chairside efficiency, enhanced esthetic outcome, and patient satisfaction., (© 2021 Wiley Periodicals LLC.)

Objective: Resin composite (RC) layering is increasingly popular in restorative dentistry. However, little is known regarding the color interaction between RC layers. The objective of this article is to review the current literature on color interaction between RC layers and its effect on the overall appearance of the double-layer restoration., Overview: A literature review was conducted on theoretical and experimental in vitro studies that tested layered RC systems using different thicknesses. This article discusses specimen design, color measurement methods and devices, parameters defined as outcomes, and RC shades and systems used in the studies of double-layered RC that were reviewed here. Relevant clinical findings and gaps that still exist in the literature were also highlighted., Conclusions: Various methods to test layered RC were found in the literature. Each study had a unique design and provided valuable information on color interaction between the enamel and dentin layers that could be applied to clinical use. For more predictable esthetic outcomes, manufacturers could provide tailored recommendations specific for their RC systems, stating the recommended thickness and shade for each layer used in the RC layering technique., Clinical Significance: With increased variability in RC shades and manufacturers, it is often difficult to predict the final overall color of restoration with multiple layers. Advancing research on RC layering will help clinicians deliver the best customized restorative treatment tailored to the needs and expectations of their patients. Future research along these lines can enhance the efficiency of chair time and will increase the satisfaction of both clinicians and patients., (© 2021 Wiley Periodicals LLC.)

In the current study, Pesticide residue extraction in beeswax was carried out using a mixture of acetonitrile-ethyl acetate (1:3, v/v). This mixture of solvents not only enables the melting of beeswax sample at a lower temperature than when using acetonitrile only but also introduces one phase solution. The sample extract was directly injected into both GC-MS/MS, of the commonly used split-less inlets, and into LC-MS/MS. Sample preparation and clean-up were also optimized. The developed method was validated according to SANTE/11813/2017 European Union guidelines. Three spiking levels of low concentrations 20, 50, 100 µg/kg were studied for the analysis of a total of 373 pesticides. Most of the studied pesticides have acceptable recovery between 80 and 110% with good reproducibility <10. There are 265 and 139 pesticides having a lower limit of quantifications equal 20 µg/kg using LC-MS/MS and GC-MS/MS, respectively. Finally, the developed method was successfully applied for the analysis of real beeswax samples., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflicts of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: To compare the color of double-layered (DL) resin-composite (RC) samples with variant enamel-thicknesses (ET) to their corresponding shade-tabs from VITA classical (VC) and 3D-Master (V3DM)., Methods: A2-DL samples (N = 30) fabricated using three pairs of custom-made molds with an ET of 0.5, 0.7, and 1.0 mm. Shades were selected according to the manufacturer's instructions of two RC brands: Clearfil-Majesty (CM), and Vita-l-essence (VL). A spectrophotometer measured CIE L*a*b* color parameters. We used ΔE 00 to calculate color differences among DL samples, VC, and V3DM shade-tabs. The data were analyzed using Spearman correlation coefficient, one-way ANOVA, and Tukey test (∝=0.05)., Results: ΔE 00 between DL samples A2 and 2M2 shade tabs were all greater than the predetermined 50:50% acceptability threshold (ΔE 00 = 6.6-10.4). Depending on the shade tabs compared, the ΔE 00 among CM and VL ET subgroups were statistically different (P < .001). ET and L* were negatively correlated for CM and VL. For CM, ΔE 00 and L* correlated on the A2 shade tab, whereas for VL, ΔE 00 , and ET correlated on the 2M2 shade tab (P < .05)., Conclusions: The DL samples produced unacceptable color matches to their corresponding shade. An enamel layer thickness of 0.7 mm corresponded to the lowest ΔE 00 . The use of V3DM for RC shade selection should be investigated., Clinical Significance: Understanding color interaction between RC layers is important to achieve consistent results in esthetic clinical procedures. The thickness of the enamel layer can critically alter the overall shade for a given RC shade and brand. This variation is difficult for the clinician to predict and negatively impacts patient satisfaction, increasing overall procedure costs, and decreasing efficiency. This color interaction study aims to facilitate consistency in shade reproduction., (© 2019 Wiley Periodicals, Inc.)

A successful oligomerization of ternary metal complexes, cobalt (II), nickel (II), copper (II), zinc (II), chromium (III) and ferric sulfate (III) with nitrilotriacetic acid (NTA) as a primary ligand and glutamic acid as a secondary ligand, has been demonstrated. The formation of oligomers arose from the presence of the sulfate moiety, which operates as a bridged bidentate ligand that coordinates with other metal moieties. The novel oligomers exhibited octahedral structures, which bonded together through the sulfate moiety. In silico predictions were conducted to gauge the bioactivity, physico-chemical and pharmacokinetic properties. The biological activities of these oligomers as well as their tumor inhibitory behavior have been explored. This work also presents a facile and novel method of preparing these materials in nanosize, using Cetyltrimethylammonium bromide (CTAB) and polyvinyl alcohol (PVA) as capping ligands. The size and shape of the nanomaterials have been confirmed using the transmission electron microscope (TEM) and the scanning electron microscope (SEM).

A facile bottom-up "green" synthetic route of gold nanoparticles (Au NPs) is described, using a leaf extract of the Malvaceae plant Corchorus olitorius as a reducing and stabilizing agent. The size and shape of the obtained nanoparticles were modulated by varying the amounts of the metal salt and the broth extract in the reaction medium. Only one hour was required for the complete conversion to Au NPs, suggesting that the reaction rate was higher or comparable to those of nanoparticles synthesized by chemical methods. The obtained nanoparticles were characterized by UV⁻visible spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, and thermal gravimetric analysis (TGA). While infrared spectroscopy was employed to characterize the various functional groups in the organic layer that stabilized the particles, TEM images were used to optimize the conditions for NPs growth. A low concentration of the C. olitorius extract yielded mixed triangular and hexagonal shapes; in contrast, quasi-spherical shapes of Au NPs with an average size of 37⁻50 nm were obtained at a higher extract broth concentration. The Au NPs displayed Surface Plasmon Resonance (SPR) bands at 535 nm. An in vitro cytotoxic assay of the biocompatible Au NPs revealed a strong cytotoxic activity in three human cancer cell lines, namely, colon carcinoma HCT-116, hepatocellular carcinoma HepG-2, and breast adenocarcinoma MCF-7. In-silico bioactivity, drug-likeness, and ADMET (Absorption, Distribution, Metabolism, Excretion, and Toxicity) predictions were conducted in order to examine the pharmacokinetic behavior of the compounds present in the C. olitorius extract.

Aim: The aim of this study is to assess the effect of 35% sodium ascorbate on microtensile bond strength of dentin immediately after bleaching with 35% hydrogen peroxide., Materials and Methods: A total of 25 sound human 3 rd molars were collected. Teeth were randomly divided into five groups for different treatments: Group I [bleaching + immediate bonding (i.e., restoration)], group II (bleaching + delayed bonding), group III (bleaching + sodium ascorbate + immediate bonding), group IV (bleaching + sodium ascorbate + delayed bonding), and group V (bonding only). After bleaching, but before bonding, groups II and IV were stored for 1 week in deionized water at 37°C. All samples were bonded using OptiBoned FL (Kerr) and Filtek Supreme (3M/ESPE). Teeth were sectioned into 1 × 1 mm 2 bars, and microtensile bond strength was tested with a universal testing machine (Instron 8841) at a cross-head speed of 0.5 mm/minute., Results: Microtensile bond strength differed significantly across the five groups, with a significant reduction in microtensile bond strength observed for samples in group I relative to samples in any of the other treatment groups (p < 0.05)., Conclusion: The application of a high concentration of sodium ascorbate for a shorter time reversed the negative effect of 35% hydrogen peroxide bleaching on composite bonding strength to dentin., Clinical Significance: The negative effects of bleaching on composite bonding can be neutralized by the application of the reversing agent sodium ascorbate thus, increasing the efficiency of clinic chair time. This is clinically relevant for those patients requiring restorative treatment immediately after in-office bleaching.

Purpose: This study was designed to find a new therapeutic modality that may have the same efficacy and lower toxicity than bacillus Calmette-Guerin (BCG) for the treatment of superficial transitional cell carcinoma of the bladder., Materials and Methods: Between January 1993 and July 1997 a prospective randomized trial was conducted on 139 patients with stages pTa and pT1 bladder transitional cell carcinoma to compare the prophylactic efficacy and toxicity of sequential BCG and epirubicin (group 1) versus BCG alone (group 2). Group 1 comprised 69 patients who received alternating doses of 150 mg. BCG and 50 mg. epirubicin (1 drug at a time), while 70 patients in group 2 received 150 mg. BCG at each instillation. Treatment was continued for 6 weeks followed by 10 monthly instillations., Results: Therapy was discontinued permanently in 3 group 1 and 12 group 2 patients due to severe side effects, and they were excluded from the study. Among the 124 evaluable patients (96 men and 28 women, mean age 58.2 years) mean followup was 30.4 months (range 12 to 50). Recurrence and progression rates were statistically comparable in both groups. Interval to first recurrence with or without progression was longer in group 1 than in group 2 (log rank p = 0.05). Toxicity and complications were significantly lower with sequential treatment than with BCG alone at rates of 27.3% (18 patients) and 70.7% (41), respectively (p = 0.001)., Conclusions: Sequential BCG and epirubicin are comparable to BCG alone in efficacy and superior in terms of toxicity.