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Objective: The objective of the study was to investigate the influence of different irrigation protocols on the shear bond strength (SBS) of self-adhesive resin cement (SARC) on primed radicular dentin., Methods: Radicular dentin slabs (N=58) were embedded in acrylic. Subsequently, they were polished and randomly assigned to five experimental groups (N=8-12) and one control group, CG (N=8). Irrigation solutions used were 2.5% sodium hypochlorite (H), 17% ethylenediamine tetraacetic acid (EDTA), 9% etidronic acid with hypochlorite (HEDP), 0.9% saline solution (SS), and 2% chlorhexidine (CHX). Each experimental group underwent a different irrigation protocol for two minutes: 1) H/EDTA/H, 2) HEDP, 3) H/EDTA/CHX, 4) H/EDTA/SS and 5) HEDP/SS. The CG samples were not treated with any irrigation solution. After drying, the adhesive-enhancing primer (AEP) and dual-curing SARC were applied to the radicular dentin using molds corresponding to the Ultra Tester (Ultradent Products, South Jordan, USA). The specimens were stored at 37 °C in distilled water and broken after 10 days in shear mode. The results were analyzed using ANOVA and post-hoc Games-Howell test, α=0.05., Results: CG exhibited the highest SBS. With the exception of HEDP and HEDP/SS, all experimental groups showed significantly lower SBS compared to CG (p<0.05)., Conclusions: HEDP appears to be an adequate solution for cleaning the root canal prior to dentin priming and fiber post cementation with SARC., Competing Interests: Conflict of interest: The authors declare no conflict of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results., (University of Zagreb School of Dental Medicine.)

This study is focused on the detailed examination of the combustion properties and kinetic analysis of a cellulose acetate fibrous bundle (CAFB), separated from used cigarette filters. It was shown that the faster rate of CAFB heating allows a large amount of heat to be supplied to a combustion system in the initial stages, where the increase in heating rate has a positive response to ignition behavior. The best combustion stability of CAFB is achieved at the lowest heating rate. Through the use of different kinetic methods, it was shown that combustion takes place through two series of consecutive reaction steps and one independent single-step reaction. By optimizing the kinetic parameters within the proposed reaction models, it was found that the steps related to the generation of levoglucosenone (LGO) (by catalytic dehydration of levoglucosan (LG)) and acrolein (by breakdown of glycerol during CAFB burning-which was carried out through glycerol adsorption on a TiO 2 surface in a the developed dehydration mechanism) represent rate-controlling steps, which are strongly controlled by applied heating rate. Isothermal predictions have shown that CAFB manifests very good long-term stability at 60 °C (which corresponds to storage in a sea shipping container), while at 200 °C, it shows a sudden loss in thermal stability, which is related to the physical properties of the sample.

With 20-80% mortality, neonatal infection caused by herpes simplex virus (HSV) or neonatal herpes is among the most severe of all perinatal infections. The majority of neonatal HSV infections are acquired during delivery, although in utero and postnatal infections do occur. Primary maternal infection is associated with a high rate of transmission (~50%), compared to

Thermo-chemical conversion via the pyrolysis of cigarette butt (CB) filters was successfully valorized and upcycled in the pre-carbonization and carbonization stages. The pre-carbonization stage (devolatilization) of the precursor material (cellulose acetate filter, r-CAcF) was analyzed by micro-scale experiments under non-isothermal conditions using TG-DTG-DTA and DSC techniques. The results of a detailed kinetic study showed that the decomposition of r-CAcF takes place via complex mechanisms, including consecutive reaction steps and two single-step reactions. Consecutive stages include the α -transition referred to as a cellulose polymorphic transformation (cellulose I → II) through crystallization mechanism changes, where a more thermodynamically ordered system was obtained. It was found that the transformation rate of cellulose I → II ('cellulose regeneration') is strongly affected by the presence of alkali metals and the deacetylation process. Two single-step reactions showed significant overlapping behavior, which involves a nucleation-controlled scission mechanism (producing levoglucosan, gaseous products, and abundant radicals) and hydrolytic decomposition of cellulose by catalytic cleavage of glycosidic bonds with the presence of an acidic catalyst. A macro-scale experiment showed that the operating temperature and heating rate had the most notable effects on the total surface area of the manufactured carbon. A substantial degree of mesoporosity with a median pore radius of 3.1695 nm was identified. The presence of macroporosity on the carbon surface and acidic surface functional groups was observed.

The aim was to evaluate the effects of Er,Cr:YSGG and/or bioactive glass 45S5 (BG) on the chemical and physical properties of enamel after radiotherapy. Third molar crowns were cut in half (buccal-lingually), and the mid part of the labial/oral surface was subjected to different protocols. All samples were treated with standard 70 Gy. After radiotherapy, enamel was treated with either Er,Cr:YSGG (2780 nm; pulse 60 μs) and BG or only BG, and control samples were kept in deionized water. Vickers microhardness, scanning electron microscopy (SEM), and characteristic X-ray spectroscopy (EDS) were performed before, after radiotherapy, and after treatment. Analysis of variance (ANOVA) was used. A significant drop in enamel microhardness was observed after radiotherapy (p < 0.001). After Er,Cr:YSGG and BG or BG alone, there was a significant increase in microhardness (p < 0.001), which was on average significantly higher compared to the initial measurements for Er,Cr:YSGG with BG (p < 0.001), but not observed in BG alone (p = 0.331). After radiotherapy, SEM showed increased surface roughness with eroded prisms. Er,Cr:YSGG and BG or BG alone both showed disorderly packed glass particles on the enamel surface. Radiotherapy noticeably reduced the concentrations of calcium and phosphorus. Er,Cr:YSGG and BG treatment increased the concentrations of calcium, sodium, phosphorus, and silicate. BG treatment alone increased the concetration of calcium and phosphorus. Directly induced radiotherapy led to potential damage of enamel, but afterwards treatment with Er,Cr:YSGG laser and BG resulted in a higher increase of enamel microhardness compared to BG alone, reflecting in a possible better remineralization effect., (© 2023. The Author(s), under exclusive licence to Springer-Verlag London Ltd., part of Springer Nature.)

Objective: The aim of this study was to examine the satisfaction of parents and caregivers of patients who underwent dental treatment in general anesthesia (GA) in a day-care surgery setting., Material and Methods: Anonymous questionnaire was sent to parents/caregivers of patients who underwent full mouth restoration in GA. The survey consisted of 4 parts: general data, data about procedure, satisfaction with various aspects of care and the perception of parents/caregivers about the condition of their child in relation to the time before dental treatment in GA., Results: 66 parents/caregivers (30.5%) responded to the questionnaire. Overall satisfaction with the treatment was high (4.69). Respondents expressed the highest degree of satisfaction with communication with nurses (4.92), and the lowest with the waiting time for the procedure (3.89). Parents/caregivers of patients who reported difficulty eating expressed significantly lower overall satisfaction than the subjects whose children did not report difficulty eating. Also, the more treatments the patients underwent, the lower was the overall satisfaction than of those subjects whose children were never treated in such a manner before., Conclusions: Since patient satisfaction has a beneficial impact on treatment outcome and adherence to preventive recommendations, all health care providers should strive to achieve it., Competing Interests: Conflict of interest The authors report no conflict of interest.

The presented paper deals with the influence of the heating rate on combustion characteristics (reactivity and reactivity evaluation, ignition index ( D i ), burnout index ( D f ), the combustion performance index ( S ), and the combustion stability index ( R W )) of the protective coronavirus face masks. Two types of commonly used face masks in different state (new and exploited) were investigated by TG-DTG analysis in an air atmosphere, directly coupled with mass spectrometry (MS). Based on the experimental results, the impact of ultimate and proximate analysis data on the evolved gas analysis (EGA) was discussed. Also, the derived values from thermo-analytical (TA) data were compared with the literature reports, related to individual constitutive face mask materials. According to the performed research, it was established that different maximal reaction rate values at various heating rates indicate the complex nature of coronavirus face mask thermo-oxidative degradation, which is stimulated with carbon oxidation reactions and volatile matter (VM) release. By detailed analysis of obtained TG-DTG profiles, it was established that process takes place through the multiple-step reaction pathways, due to many vigorous radical reactions, causes by polymers degradation. The performed research was done to evaluate the possible utilization of coronavirus waste to energy production and sustainable pandemic environmental risk reduction., Competing Interests: Conflict of interestThe 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., (© Akadémiai Kiadó, Budapest, Hungary 2022.)

Ambroxol hydrochloride (AMB), used as a broncho secretolytic and an expectorant drug, is a semi-synthetic derivative of vasicine obtained from the Indian shrub Adhatoda vasica . It is a metabolic product of bromhexine. The paper provides comprehensive and detailed research on ambroxol hydrochloride, gives information on thermal stability, the mechanism of AMB degradation, and data of practical interest for optimization of formulation that contains AMB as an active compound. Investigation on pure AMB and in commercial formulation Flavamed ® tablet (FT), which contains AMB as an active compound, was performed systematically using thermal and spectroscopic methods, along with a sophisticated and practical statistical approach. AMB proved to be a heat-stable and humidity-sensitive drug. For its successful formulation, special attention should be addressed to excipients since it was found that polyvinyl pyrrolidone and Mg stearate affect the thermal stability of AMB. At the same time, lactose monohydrate contributes to faster degradation of AMB and change in decomposition mechanism. It was found that the n-th order kinetic model mechanistically best describes the decomposition process of pure AMB and in Flavamed ® tablets.

A commonly used approach to enhance the dissolution of drugs with pH-dependent solubility is the incorporation of pH modifiers. The aim of this study was to evaluate the duration and extent of pH modifying effect on the micro-environmental pH in HPMC matrix by applying two mechanistic approaches regarding hydrodynamic stress on the tested formulation (i.e. static dissolution apparatuses (USP2) and dynamic approaches including the Advanced gastric simulator (AGS) and the Intestinal model for simulation of peristaltic action (IMSPA)). Moreover, the aim of our research was also the preparation of sustained-release matrix systems with improved - enhanced drug dissolution. In our study, the occurrence of a pH gradient in the gel layer of the HPMC tablets was observed during simulation of their passage along different compartments of the GIT. The pH gradient was affected by the media composition and duration of tablet exposure to the surrounding media. Both dissolution methods were also used to evaluate the influence of the mechanical stress on the drug release kinetics. Micro-environmental pH (pH M ) was evaluated, using two methods: the cryostatic method with a surface pH electrode, and with the incorporation of a pH sensitive dye (methyl orange) into the matrix tablets. Our study demonstrates a significantly higher dissolution rate due to mechanical stress during the bio-relevant simulation of GIT transit of the mechanically sensitive HPMC tablets with poorly soluble drugs. A considerably higher release rate was also observed from tablets with the weakly basic drugs dipyridamole and propranolol hydrochloride containing pH modifier in case of mechanically bio-relevant dissolution models compared to the USP2 apparatus. For the assessment of the pH M , the incorporation of a pH indicator dye in the HPMC tablet proved to be more suitable, while the cryostatic method was found to be useful only for a rough pH M estimation., (Copyright © 2021 Elsevier B.V. All rights reserved.)

This article describes the designing of matrix tablets composed of polyethylene oxides (PEOs) with relative molecular masses of 1 × 106, 2 × 106, and 4 × 106. Percolation thresholds were determined for all of the selected PEO formulations (18, 16, and 12 %, m/m), taking into consideration excipients and tablet surface area which significantly increased the percolation threshold. Moreover, the robustness of the gel layer in PEO matrix tablets was evaluated by magnetic resonance imaging under various mechanical stresses (no flow, 12 mL min-1, and 64 mL-1 of medium flow). Correlations between the percolation threshold and gel thickness (R2 = 0.86), gel thickness and the erosion coefficient (R2 = 0.96) was detected. Furthermore, small-angle X-ray scattering of the selected PEOs detected differences in polymer molecular complexity at the nanoscale. Finally, the ratio of the heat of coalescence to the heat of fusion has confirmed the PEO molecular mass-dependent percolation threshold.

Objective: To review the frequency and management of post-discharge complications in patients who underwent dental treatment in general anesthesia (GA) in a day-care surgery setting and identify the factors that increase the risk for these complications., Material and Methods: Anonymous questionnaire was sent to parents/caregivers of patients who underwent full mouth restoration in GA at our institution between 1 st January 2017 and 31 st July 2019. Demographic and clinical data of patients as well as the data about the occurrence and management of complications were collected., Results: Sixty-six parents/caregivers (30.5%) responded to the questionnaire. Most frequent complications were drowsiness and pain in 40(60.6%) patients. Complications were managed by parents or caregivers with conservative measures at home in 57(91.9%) cases. Phone consultation with dentist was required in 5(8.1%) cases. One patient (1.6%) was readmitted. Younger age and diagnosis were associated with increased risk for drowsiness., Conclusion: Post discharge complications of dental treatment in GA in a day-care service are common and they can be managed by parent/caregiver with conservative measures at home. The rate of readmission is low. Dental treatment in GA in a day-care service is a safe procedure that can be performed with acceptable risk in carefully selected patients., Competing Interests: Conflict of interest statement The authors declare no conflict of interestConflict of interest None declared