Corrigendum: Risk of Dental Caries and Erosive Tooth Wear in 117 Children and Adolescents' Anorexia Nervosa Population-A Case-Control Study

[This corrects the article DOI: 10.3389/fpsyt.2022.874263.].

Risk of Dental Caries and Erosive Tooth Wear in 117 Children and Adolescents' Anorexia Nervosa Population-A Case-Control Study

INTRODUCTION

Restrictive type of anorexia nervosa (AN) is still one of the most severe eating disorders worldwide with an uncertain prognosis. Patients affected by AN should be encouraged to undertake psychiatric care and psychotherapy, but whether they should necessarily be included in careful dental care or not may still be questionable. Even though there is a constantly increasing number of AN studies, there are just a few data about the youngest group of AN children and adolescents aged < 18.

METHODOLOGY

This case-control study aimed to compare the dental health and gingival inflammation level in female adolescent inpatients affected by severe AN restrictive subtype vs. controls. Based on clinically confirmed 117 AN cases (hospitalized in years 2016-2020 in public Psychiatric Unit, BMI < 15 kg/m², mean age 14.9 ± 1.8), the dental status has been examined regarding the occurrence of caries lesions using Decay Missing Filling Teeth (DMFT), erosive wear as Basic Erosive Wear Examination (BEWE), gingival condition as Bleeding on Probing (BOP) and plaque deposition as Plaque Control Record (PCR). The results were compared with age-matched 103 female dental patients (BMI 19.8 ± 2.3 kg/m², age 15.0 ± 1.8, p = 0.746) treated in a public University dental clinic.

RESULTS

AN patients were found to present a higher incidence of oral-related complications according to dental status (DMFT 3.8 ± 4.5 vs. 1.9 ± 2.1, p = 0.005), erosive tooth wear (BEWE 18.9 vs. 2.9%, p < 0.001), less efficient in controlling plaque (PCR 43.8 vs. 13.7%, p < 0.001) and gingival inflammation (BOP 20.0 vs. 3.9%, p < 0.001) compared with female adolescents. In the AN group, a significant correlation between BOP, BEWE, and duration of AN disease (p < 0.05), similarly to the number of decayed teeth D, filled teeth F and PCR were detected (p < 0.05).

CONCLUSIONS

Although the obtained results did not reveal any severe oral status, our findings indicated impaired dental and gingival conditions in young anorexics. Considering AN's potential role in oral health, it is essential to monitor dental treatment needs and oral hygiene levels in their present status to prevent forward complications in the future.

Assessment of Erosion Characteristics in Purple and Yellow Soils Using Simulated Rainfall Experiments

Soil erosion of sloped lands is one of the important sources of substantive sediments in watersheds. In order to investigate erosion characteristics of sloped lands during rainfall events in the Three Gorges Reservoir Area, erosion processes of purple and yellow soils under different slope gradients and rainfall intensities were studied by using a rainfall simulator. The results showed that the sediment concentration in runoff was closely correlated with rainfall intensity. The sediment concentration in runoff gradually rose to a peak with time, and then gradually declined and approach a steady rate during simulation rainfall events. The particle size distribution of surface soils before the rainfall was different from that after the rainfall. Soil erosion mainly resulted in the loss of fine particles of surface soil through runoff, and the fine particles of soil were enriched in sediments. Soil erosion rates were gradually increased with the slope gradient when the slope gradient was less than 10°, and significantly increased when the slope gradient was more than 10°. The slope factor of yellow soil could be fitted well to that calculated by the formula of Universal Soil Loss Equation (USLE). The trend of the slope factor of purple soil was similar to that of the slope factor that was derived from USLE. Therefore, the effect of slope gradients on soil erosion need to be further researched when USLE was applied to predict erosion in purple soil area.

Influence of Some Microchanges Generated by Different Processing Methods on Selected Tribological Characteristics

Different processing methods can change the physical-mechanical properties and the microgeometry of the surfaces made by such processes. In turn, such microchanges may affect the tribological characteristics of the surface layer. The purpose of this research was to study the tribological behavior of a test piece surfaces analyzing the changes on the values of the coefficient of friction and loss of mass that appear in time. The surfaces subjected to experimental research were previously obtained by turning, grinding, ball burnishing, and vibroburnishing. The experimental research was performed using a device adaptable to a universal lathe. Mathematical processing of the experimental results led to the establishment of power-type function empirical models that highlight the intensity of the influence exerted by the pressure and duration of the test on the values of the output parameters. It was found that the best results were obtained in the case of applying ball vibroburnishing as the final process.

Abrasion and Erosion Resistance of Cermets: A Review

WC-based hardmetals are employed widely as wear-resistant ceramic-metal composites for tools and wear parts. Raw materials supply, environmental concerns and some limitations of hardmetals have directed efforts toward development of alternative wear-resistant composites-cermets. We present a current state of knowledge in the field of ceramic-rich (≥50 vol%) cermets behavior in abrasion and erosion conditions, which are the dominant types of wear in many industrial applications. Distinction is made between two-body and three-body abrasion, solid-particle erosion, and slurry erosion. Cermets, in particular TiC-, Ti(C,N)- and Cr₃C₂-based composites and hardmetals, are compared for their abrasive and erosive wear performance and mechanism. The review enabled formulation of tribological conditions in which cermets may be comparable or have potential to outperform WC-Co hardmetals. Hardmetals, in general, outperform cermets in abrasion and solid-particle erosion at room and moderate temperatures. However, cermets demonstrate their potential mainly in severe conditions-at elevated temperatures and corrosive (oxidation, electrochemical corrosion) environments.

Design and evaluation of a zero-order controlled release system based on pre-hydrated constant release area prepared by compression coating technology

The main aim of this research work was to develop and evaluate a drug delivery system with compression coating technology to control drug release at a constant rate. The compression coated tablets (CCTs) consist of the hydrophilic matrix core and the hydrophobic waxy coating. The presence of hydrophobic waxy coating could provide sufficient time for hydration of the core to prevent initial burst release. The mechanism research revealed that erosion was the main way of drug release and the releasing area was constant during the entire release process because the core tablet was located in the cup-shaped coating after one side cover was dropped at the lag time. This made the release behavior exhibit zero-order kinetics (R²>0.99). The coating rupture strength and the core swelling force at the lag time influenced erosion rate thus affecting release rate. Different solubility of drugs (propranolol hydrochloride, melatonin, and nifedipine) was selected as model drugs and the properties of the prepared CCTs in terms of formulations and in vitro release were evaluated. The release rate was independent of solubility, medium pH, and osmotic pressure. This zero-order controlled system could be applied to both controlled drug delivery and chrono pharmaceutical drug delivery.

Tooth Wear Evaluation System (TWES) 2.0-Reliability of diagnosis with and without computer-assisted evaluation

BACKGROUND

Tooth wear is a multifactorial process, leading to the loss of dental hard tissues. Therefore, it is important to detect the level of tooth wear at an early stage, so monitoring can be initiated. The Tooth Wear Evaluation System (TWES) enables such a multistage diagnosis of tooth wear. The further developed TWES 2.0 contains a complete taxonomy of tooth wear, but its reliability has not yet been validated.

OBJECTIVES

The aim of the study was to examine in a randomised controlled trial (RCT) whether diagnoses made based on the TWES 2.0 are reproducible and whether this reproducibility is also achieved with computer-assisted diagnostics.

METHODS

44 dental students received extensive training in TWES 2.0 assessment and taxonomy. The students each evaluated at least 10 (of the present 14) anonymised patient cases using gypsum models and high-resolution intra-oral photographs according to TWES 2.0. One half initially evaluated on paper; the other half used dedicated software (CMDfact / CMDbrux). After half of the patient cases (5), the evaluation methods were switched (AB/BA crossover design). The diagnoses were then evaluated for agreement with the predefined sample solution.

RESULTS

Evaluation of agreement with the sample solution according to Cohen's kappa indicated a value of 0.46 for manual (traditional) evaluation; and 0.44 for computer-assisted evaluation. Evaluation of agreement between examiners was 0.38 for manual and 0.48 for computer-assisted evaluation (Fleiss' kappa).

CONCLUSION

The results of this study proved that the taxonomy of the TWES 2.0 has acceptable reliability and can thus be used by dentists. Accordingly, the system can be learned quickly even by untrained practitioners. Comparable results are achieved with computer-assisted evaluation.

A digital workflow with the virtual enamel evaluation and stereolithographic template for accurate tooth preparation to conservatively manage a case of complex exogenous dental erosion

OBJECTIVE

This article describes a digital workflow using virtual enamel evaluation and a stereolithographic template for accurate tooth preparation for a complex exogenous dental erosion.

CLINICAL CONSIDERATIONS

A 22-year-old man with different degrees of defects on the labial surface in esthetic area was diagnosed as exogenous dental erosion. The residual undamaged enamel area and depth of defect were measured and analyzed accurately by creating a digital virtual patient based on the pretreatment data. According to the different conditions of residual enamel and tooth defect, the treatment plans of porcelain veneer, crown and composite resin were chosen for corresponding involved teeth. Based on the virtual wax-up and the suggested material thickness, a template for tooth preparation was designed and three-dimensional printed. This template together with a special bur indicating the reduction depth accurately guided the teeth preparation and achieved a long-term effect.

CONCLUSIONS

The virtual enamel evaluation contributes to obtaining the appropriate corresponding treatment plan objectively. The stereolithographic template effectively meets the accuracy of tooth preparation, preserving the tooth hard tissue to the greatest extent.

CLINICAL SIGNIFICANCE

The digital workflow described here may provide a quantifiable evaluation method and an accurate tooth preparation method for exogenous dental erosion.

Understanding Variations in the Tracking and Erosion Performance of HTV-SR-Based Composites due to AC-Stressed Aging

Among the polymeric family, high-temperature-vulcanized silicone rubber (HTV-SR) is the most deployed material for high voltage insulation applications. However, in an outdoor environment, due to contamination and wetting-induced dry band arcing, consequently SR experiences surface tracking and erosion. From a practical standpoint, the tracking and erosion performance under multi-stress aging is required to be known. It is in that context that the present study was undertaken to measure and analyze the effect of multi-stress aging on tracking and erosion performance. Composite samples of SR having different filler concentrations of silica and alumina trihydroxide (ATH) were aged in a multi-stress chamber for a period of 5000 h, and after that their electrical tracking performance was studied. Simultaneously, unaged samples were also exposed to tracking test for comparison. To conduct this test, the inclined plane testing technique was used in accordance with IEC-60587. All samples exposed to tracking test were analyzed using different diagnostic and measuring techniques involving surface leakage current measurement, Fourier transform infrared spectroscopy (FTIR), thermal stability and hydrophobicity classification. Experimental results shown that the tracking lifetime increased through incorporation of silica and ATH fillers in the SR. Amongst all test samples, two samples designated as filled with 2% nano silica and 20% micro silica/ATH exhibited greater resistance to tracking. This was attributed to the optimum loading as well as better dispersion of the fillers in the polymer matrix. The presence of nano-silica enhanced time-to-tracking failure, owing to both improved thermal stability and enhanced shielding effect on the surface of nanocomposite insulators.

Effectiveness of Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) Compared to Fluoride Products in an In-Vitro Demineralization Model

The goal of this study was to evaluate the effectiveness of the toothpaste Tooth Mousse compared to conventional fluoride-based versions in the prevention of enamel and dentin demineralization. Human enamel and dentin samples (n = 120 each) were exposed to artificial demineralization at pH 4.92. During the demineralization process, the samples in the test groups were periodically treated with Tooth Mousse (TM) containing casein-phosphopeptide -amorphous-calcium-phosphate (CPP-ACP) and Tooth Mousse Plus (TMP) containing amorphous-calcium-fluoride-phosphate (CPP-ACPF) to evaluate their protective properties. Fluoride toothpastes containing 1400 ppm amine fluoride (AmF) and 1450 ppm sodium fluoride (NaF) were applied in the positive control groups. Treatment with distilled water (group C-W) or demineralization without treatment (group C-D) served as negative controls. After the demineralization and treatment process, all samples were cut longitudinally and lesion depths were determined at six locations using polarized light microscopy. In TM/TMP groups (enamel: 80/86 µm, dentin: 153/156 µm) lesion depths were significantly smaller compared to the negative control groups C-W/C-D (enamel: 99/111 µm, dentin: 163/166 µm). However, TM and TMP compared to the positive controls AmF/NaF (enamel: 58/63 µm, dentin: 87/109 µm) showed higher lesion depths. The application of TM/TMP (89%/78%) during demineralization led to a reduced number of severe lesions compared to the negative controls C-W/C-D (100%/95%). In this study we demonstrate that Tooth Mousse is less effective regarding prevention of enamel and dentin demineralization compared to fluoride containing toothpastes.

Optical Coherence Tomography of Plaque Erosion: JACC Focus Seminar Part 2/3

Plaque erosion, a distinct histopathological and clinical entity, accounts for over 30% of acute coronary syndromes (ACS). Optical coherence tomography allows in vivo diagnosis of plaque erosion. Local flow perturbation with activation of Toll-like receptor 2 and CD8⁺ T cells and subsequent desquamation of endothelium and neutrophil extracellular trap formation contribute to mechanisms of plaque erosion. Compared with ACS patients with plaque rupture, those with plaque erosion are younger, have fewer traditional cardiovascular risk factors, have lower plaque burden, and are more likely to present with non-ST-segment elevation ACS. Early evidence suggests that in patients with ACS caused by plaque erosion, antithrombotic therapy without stenting may be a safe and effective option. Future randomized trials are needed to validate these findings. Clinical studies to develop noninvasive point-of-care biomarkers that distinguish plaque rupture from erosion, and to test novel therapies that target molecular pathways involved in plaque erosion are needed.

Global Assessment of Agricultural Productivity Losses from Soil Compaction and Water Erosion

To guide us toward a sustainable future, the impacts of human activities on natural resources need to be understood and quantified. In this study on global agriculture, we use a Life Cycle Assessment framework to estimate potential long-term soil productivity losses caused by soil compaction and water erosion due to agricultural crop production. We combine several data sets to model spatially resolved Life Cycle Inventory information at the global level and multiply results with characterization factors from a previous publication. The global picture shows a compaction-stressed "Global North" and an erosion-stressed "Global South", with some countries and regions in between, for example, China and parts of South America. Results show that both compaction and water erosion impacts matter at the global level and that overall potential long-term productivity losses of 10-20% can be expected, with high relative impacts on low input production systems. These losses might limit long-term agricultural productivity and lead to additional land use change. Our work adds to and extends the discussion of global assessments of soil degradation. Furthermore, we prove the suggested framework to be applicable and useful for Life Cycle Assessments and other studies and provide results that can be used in such global assessments.

Homemade Modification of Salad Dressings to Reduce Their Erosive Potential

PURPOSE

To investigate the possibility of reducing the erosive potential of salad dressings by adding yoghurt.

MATERIALS AND METHODS

Two hundred enamel samples from bovine teeth were allocated to 20 groups (n = 10). Three modified commercially available balsamic dressings (addition of 10%, 20%, 50% yoghurt or 8.8 mM calcium chloride) and two homemade salad dressings with and without modifications were tested. Enamel samples were eroded for 2 min, rinsed for 30 s with tap water and finally abraded (20 brushing strokes with toothpaste slurry). After 40 of these cycles of erosion/abrasion, the dental hard tissue loss was determined by contact profilometry.

RESULTS

For commercially available salad dressings, modification yielded a statistically significant decrease in enamel wear. The exception was Anna's Best Dressing Balsamico modified with 8.8 mM calcium chloride, for which no reduction was found compared with the unmodified dressing. For all homemade dressings, a significant reduction was observed when modified with 20% yoghurt. However, when only 10% yoghurt was added to the homemade dressings, an increase of the erosive potential was observed compared to the unmodified dressing.

CONCLUSIONS

The study shows that increasing the calcium concentration only with calcium chloride in commercially available salad dressings did not show predictable outcomes to reduce erosion. However, mixing 20% plain yoghurt into the dressings reduced the erosive potential statistically significantly.

Bone erosions and osteophytes in premenopausal women with long-standing rheumatoid arthritis: association with systemic bone involvement by HR-Pqct

OBJECTIVE

To evaluate premenopausal women with long-standing RA and to explore the relationship between parameters of systemic and localized bone involvement.

METHODS

Eighty consecutive RA premenopausal women were evaluated. Volumetric bone mineral density (vBMD), microarchitecture and finite element analysis were performed using high-resolution peripheral quantitative computed tomography (HR-pQCT) at the distal radius (DR) and tibia (DT) and compared with parameters from 160 female healthy controls matched by age and body mass index. Localized bone involvement was also analyzed using HR-pQCT in the metacarpophalangeal and proximal interphalangeal joints to identify erosions and osteophytes.

RESULTS

The mean age of RA patients was 39.4±6.7years and disease duration 9.8±5.3years. RA patients had impaired trabecular, cortical and bone strength parameters, at DR and DT, compared with healthy controls (p<0.05). Bone erosions and osteophytes were found in 75% and 41.3% of patients, respectively. Comparing patients with and without erosions, at DR and DT, a lower cortical vBMD (DR: 980±72 versus 1021±47mgHA/cm³ , p=0.03; DT:979±47 versus 1003±34 mgHA/cm³ , p=0.04) and higher cortical porosity (DR:2.8±2.5 versus 1.8±1.6%, p=0.04; and DT:3.7±1.6 versus 2.7±1.6%, p=0.01) were observed in patients with erosions. At the DR, osteophyte volume was positively correlated with trabecular vBMD (0.392, p=0.02), trabecular number (0.381, p=0.03) and stiffness (0.411, p=0.02), and negatively with trabecular separation (-0.364, p=0.04).

CONCLUSION

Our findings showed that premenopausal women with long-standing RA had systemic bone fragility at peripheral sites. Moreover, erosions were associated mainly with cortical bone fragility at the DR and DT, and osteophytes correlated with repair of trabecular bone at the radius.

Response and Deterioration Mechanism of Bitumen under Acid Rain Erosion

Acid rain as an important environmental issue has a negative impact on bitumen performance, thereby shortening the service life of asphalt pavements. Thus, this research aims to investigate the response of bitumen to acid rain and its deterioration mechanism. For this purpose, the simulated acid rain was prepared to erode neat bitumen and short-term aged bitumen. The hydrogen ion concentration of the acid rain, and the morphological, physical, chemical, and rheological properties of the bitumen were evaluated by means of a pH meter, scanning electron microscopy, physical tests, Fourier transform infrared radiation with attenuated total reflectance, and dynamic shear rheometer. The results showed that bitumen properties were severely affected by acid rain, and the changes in bitumen properties were highly related to the erosion time, leading to a reduction in pH value by 0.2 of residual acid rain, rougher bitumen surface, and stiffer bitumen with more oxygen-containing functional groups and fewer carbonyl acid groups (around 10% decrement) after 90 days erosion. These changes contributed to two deterioration mechanisms: oxidation and dissolution of carbonyl acid. Oxidation and dissolution are, respectively, the dominant actions for neat bitumen and aged bitumen during the erosion process, which eventually leads to various responses to acid rain.

Expansion of CD4+CD8+ Double-positive T cells in Rheumatoid Arthritis Patients is Associated with Erosive Disease

OBJECTIVES

CD4+CD8+ double-positive (DP) T cells are expanded in the peripheral blood of a subset of patients with rheumatoid arthritis (RA). This study examines the clinical significance of DP T cells in RA.

METHODS

In 70 RA patients, DP T cells were measured by flow cytometry. Clinical data were obtained, and hand and feet radiographs were scored according to the Sharp/van der Heijde (SvdH) method. The association between DP T cell frequency and erosive joint destruction was analyzed by correlation and multiple logistic regression analysis.

RESULTS

Nineteen RA patients (27.1%) displayed increased DP T cell frequencies, which correlated with age (r = 0.288, p= 0.016). Expansion of DP T cells was associated with the occurrence of erosions (94,7% vs 43,1%, p< 0.001), with a higher SvdH joint damage score (24.5 vs 6, p= 0.008) and with more frequent use of biologic or targeted-synthetic DMARDs (68.4% vs 38%, p= 0.02). In patients with non-erosive disease, DP T cell frequencies correlated with the joint space narrowing score (n = 28, r = 0.44, p= 0.02). Logistic regression revealed DP T cells to be associated with erosive disease (OR 1.90, p< 0.05).

CONCLUSION

Expansion of DP T cells is associated with joint damage and frequent escalation of therapy, possibly suggesting a contribution to more severe RA.

Assessment of radiographic progression in patients with rheumatoid arthritis treated with tofacitinib in long-term studies

OBJECTIVES

Tofacitinib is an oral Janus kinase inhibitor for the treatment of RA. We evaluated radiographic progression in tofacitinib-treated patients with RA for up to 3 years in two pooled long-term extension (LTE) studies (ORAL Sequel; A3921041) (primary analysis), and for up to 5 years using data integrated from one phase (P)2 (A3921068), two P3 (ORAL Start; ORAL Scan) and two LTE studies (exploratory analysis).

METHODS

In LTE studies, patients received tofacitinib 5 mg twice daily (BID) or 10 mg BID as monotherapy or with conventional synthetic (cs)DMARDs. Radiographic outcomes up to 3 years: least squares mean (LSM) change from baseline in van der Heijde modified Total Sharp Score (ΔmTSS), erosion score (ΔES) and joint space narrowing (ΔJSN) score; proportion of patients with no radiographic progression (ΔmTSS ≤0.5); proportion of patients with no new erosions (ΔES ≤0.5). ΔmTSS was evaluated for up to 5 years in an exploratory analysis.

RESULTS

For all tofacitinib-treated patients with radiographic data available at LTE month 36 (n = 414), LSM ΔmTSS was 1.14, LSM ΔES was 0.66, LSM ΔJSN was 0.74, and 74.3% and 86.2% of patients showed no radiographic progression and no new erosions, respectively. Similar values were observed regardless of tofacitinib dose, or whether patients received tofacitinib as monotherapy or with csDMARDs. In an exploratory analysis of integrated P2/P3/LTE studies, LSM ΔmTSS was 3.34 at month 60 (n = 269).

CONCLUSION

Limited progression of structural damage was observed in tofacitinib-treated patients up to 5 years, with similar results for tofacitinib used as monotherapy or combination therapy up to 3 years.

TRIAL REGISTRATION

ClinicalTrials.gov (http://clinicaltrials.gov): NCT01164579; NCT01039688; NCT00847613; NCT00413699; NCT00661661.

Topography of Bone Erosions at the Metatarsophalangeal Joints in Rheumatoid Arthritis: Bilateral Mapping by Computed Tomography

OBJECTIVES

To describe the bilateral anatomical location of bone erosions (BE) at the metatarsophalangeal joints in patients with rheumatoid arthritis using computed tomography.

MATERIALS AND METHODS

Eighteen consecutive patients with established rheumatoid arthritis prospectively underwent computed tomography of both forefeet. Each joint surface of the metatarsal heads (MTH) and the proximal phalangeal bases were divided into four quadrants: superior, plantar, tibial, and fibular. The number of BE was cumulatively counted per patient, side, joint, per joint surface, and quadrant. Descriptive statistics, paired and unpaired samples t-tests, Pearson's correlation coefficients, ANOVA 2, and variance component analysis were performed.

RESULTS

There were 288 BE at the MTH and 66 at the proximal phalanges. The number of BE in one forefoot was a poor predictor of the absolute number of BE on the contralateral foot "r=0.54" and was unrelated to symptoms. The superior quadrants were less frequently affected than other quadrants for both the MTH "p<0.0001" and proximal phalanges "p<0.001." The tibial quadrant showed a higher number of BE compared to all other quadrants for MTH "p<0.03," proximal phalanges "p<0.01, and for the metatarsophalangeal joint as a whole "p<0.0001." Plantar and fibular quadrants were equally affected "p<0.05."

CONCLUSION

BE were found more frequently on the tibial side of the MTH in patients with rheumatoid arthritis.

Erosion and Corrosion Resistance Performance of Laser Metal Deposited High-Entropy Alloy Coatings at Hellisheidi Geothermal Site

Geothermal process equipment and accessories are usually manufactured from low-alloy steels which offer affordability but increase the susceptibility of the materials to corrosion. Applying erosion-corrosion-resistant coatings to these components could represent an economical solution to the problem. In this work, testing of two newly developed laser metal deposited high-entropy alloy (LMD-HEA) coatings-CoCrFeNiMo_0.85 and Al_0.5CoCrFeNi, applied to carbon and stainless steels-was carried out at the Hellisheidi geothermal power plant. Tests in three different geothermal environments were performed at the Hellisheidi site: wellhead test at 194 °C and 14 bar, erosion test at 198 °C and 15 bar, and aerated test at 90 °C and 1 bar. Post-test microstructural characterization was performed via Scanning Eletron Microscope (SEM), Back-Scattered Electrons analysis (BSE), Energy Dispersive X-ray Spectroscopy (EDS), optical microscopy, and optical profilometry while erosion assessment was carried out using an image and chemical analysis. Both the CoCrFeNiMo_0.85 and Al_0.5CoCrFeNi coatings showed manufacturing defects (cracks) and were prone to corrosion damage. Results show that damage in the CoCrFeNiMo_0.85-coated carbon steel can be induced by manufacturing defects in the coating. This was further confirmed by the excellent corrosion resistance performance of the CoCrFeNiMo_0.85 coating deposited onto stainless steel, where no manufacturing cracks were observed.

Aesthetic Management of Erosive Tooth Wear in a Young Egyptian Swimmer: A Case Report

Background

Tooth wear can have a multifactorial aetiology which requires thorough patient assessment and aesthetic management.

Purpose

This case report discusses the management of a young, Egyptian swimmer complaining of tooth sensitivity associated with erosive tooth wear. Anterior teeth were restored using the injection molding technique, also known as the injectable composite resin technique, to overcome the patient’s complaint and enhance the aesthetics of compromised anterior teeth.

Patients and Methods

Thorough patient assessment was followed by impression taking, a diagnostic wax-up and intraoral mock-up fabrication for aesthetic, functional and biological verification. Upon the patient’s agreement on the proposed treatment, an injection molding technique was carried out.

Conclusion

The tooth loss pattern associated with erosive tooth wear in competitive swimmers showed a very characteristic presentation. Detailed patient history is imperative for successful assessment of the risk factors contributing to the condition and treatment planning in such cases. The use of injection molding technique for restoration of anterior teeth is a simple, straightforward and aesthetically pleasing alternative for patients with erosive tooth wear requiring direct composite veneers.

Future carbon emissions from global mangrove forest loss

Mangroves have among the highest carbon densities of any tropical forest. These 'blue carbon' ecosystems can store large amounts of carbon for long periods, and their protection reduces greenhouse gas emissions and supports climate change mitigation. Incorporating mangroves into Nationally Determined Contributions to the Paris Agreement and their valuation on carbon markets requires predicting how the management of different land-uses can prevent future greenhouse gas emissions and increase CO₂ sequestration. We integrated comprehensive global datasets for carbon stocks, mangrove distribution, deforestation rates, and land-use change drivers into a predictive model of mangrove carbon emissions. We project emissions and foregone soil carbon sequestration potential under 'business as usual' rates of mangrove loss. Emissions from mangrove loss could reach 2391 Tg CO_2 eq by the end of the century, or 3392 Tg CO_2 eq when considering foregone soil carbon sequestration. The highest emissions were predicted in southeast and south Asia (West Coral Triangle, Sunda Shelf, and the Bay of Bengal) due to conversion to aquaculture or agriculture, followed by the Caribbean (Tropical Northwest Atlantic) due to clearing and erosion, and the Andaman coast (West Myanmar) and north Brazil due to erosion. Together, these six regions accounted for 90% of the total potential CO_2 eq future emissions. Mangrove loss has been slowing, and global emissions could be more than halved if reduced loss rates remain in the future. Notably, the location of global emission hotspots was consistent with every dataset used to calculate deforestation rates or with alternative assumptions about carbon storage and emissions. Our results indicate the regions in need of policy actions to address emissions arising from mangrove loss and the drivers that could be managed to prevent them.

Studying Drug Release through Polymeric Controlled Release Formulations in United States Pharmacopoeia 2 Apparatus Using Multiphysics Simulation and Experiments

In vitro dissolution of oral drug formulations is often studied using the United States Pharmacopoeia (USP) apparatus. Although a well-stirred vessel or a perfect sink assumption is often employed in the modeling of in vitro dissolution in USP apparatus, such a limit is usually not realized in actual experimental conditions. The interplay of hydrodynamics in the vessel and the swelling and erosion of dosage forms often results in substantial deviations from the dissolution behavior obtained under perfect sink approximation. We develop a multiphysics model of drug release from controlled release tablets of polymeric excipients with active pharmaceutical ingredients (APIs). Simulations are performed in COMSOL for the USP 2 (paddle) apparatus and the effects of stirring speed, drug loading, erosion rate, and polymer swelling and erosion are analyzed in detail. We demonstrate that the drug release phenomena can be conveniently interpreted using the Weibull equation to fit the simulation results. This is further confirmed using drug release experiments performed on mechanically compressed tablets of naproxen sodium as the API with poly-methyl-methacrylate-co-methacrylic acid as the excipient. We show that the API-to-polymer ratio may be varied to obtain different regimes of controlled release.

Safety and In Situ Antierosive Effect of CaneCPI-5 on Dental Enamel

The sugarcane cystatin (CaneCPI-5) was recently cloned and showed strong binding force to dental enamel and protection against initial erosion. However, evaluations on its safety and efficacy in a situation closer to the clinical condition are necessary. In the present study we analyzed 1) the cytotoxicity of CaneCPI-5 on human gingival fibroblasts (HGFs); 2) the ability of CaneCPI-5 to reduce enamel erosion and erosion+abrasion in situ. In part 1, HGFs were treated with CaneCPI-5 (0.025, 0.05, 0.1, 0.5 or 1.0 mg/mL) or no treatment (control). The cytotoxicity was assessed after 60 s and 24 h by mitochondrial activity (MTT), confocal microscopy, and hematoxylin/eosin staining. In part 2, 15 volunteers participated in a double-blind crossover protocol consisting of 3 phases, according to the following treatments: 1) 0.1 mg/mL CaneCPI-5; 2) SnCl₂/NaF/AmF (Elmex; positive control); 3) water (negative control). The volunteers wore an appliance containing 4 bovine enamel specimens for 5 d. Each day, the specimens were individually treated with 50 µL of the tested solutions per 60 s and then subjected to erosive challenges (0.1% citric acid, pH 2.5, for 90 s, 4 times per day). After the first and last erosive challenge each day, 2 samples were abraded (toothbrushing, 15 s). Enamel wear was measured by contact profilometry. One or two-way analysis of variance (ANOVA)/Tukey's or Sidak's tests (P < 0.05) were applied. Regardless of the concentration and the experimental time, CaneCPI-5 did not decrease the cell viability compared to the negative control (P < 0.05). Erosion+abrasion led to significantly greater wear compared to erosion only. For both conditions, the lowest wear was found for SnCl₂ and CaneCPI-5, which did not differ significantly from each other, but showed significant protection when compared to the negative control. In conclusion, CaneCPI-5 is safe on HGFs and reduces enamel erosive wear to the same extent as a commercial solution used to control erosive tooth wear (ETW).

Effect of Modifications in Poly (Lactide-co-Glycolide) (PLGA) on Drug Release and Degradation Characteristics: A Mini Review

The use of PLGA in the pharmaceutical industry has only increased as we move towards more and more advanced delivery carrier systems. The qualities of PLGA like biocompatibility, biodegradability and a tunable degradation and drug release has only helped in keeping up the release requirements desired for various delivery platforms. Fine-tuning the release and degradation rate is gaining more and more attention as researchers keep pushing the boundaries of novel delivery carriers. Various experiments are being performed to understand the degradation behavior drug of PLGA under various physiological and process-related conditions. The understanding of these parameters has helped formulate various ways one can fine-tune the properties that can lead to the release of active ingredients encapsulated within. Various techniques have been tried and tested including modifications like chemical modifications, physical blending and surface modifications and have found to be effective means of release modulation in delivery systems like parenteral, orals, topicals and tissue engineering scaffolds. In this review, all these experiments and implications thereon have been discussed in detail.

Grassland-to-cropland conversion increased soil, nutrient, and carbon losses in the US Midwest between 2008 and 2016

After decades of declining cropland area, the United States (US) experienced a reversal in land use/land cover change in recent years, with substantial grassland conversion to cropland in the US Midwest. Although previous studies estimated soil carbon (C) loss due to cropland expansion, other important environmental indicators, such as soil erosion and nutrient loss, remain largely unquantified. Here, we simulated environmental impacts from the conversion of grassland to corn and soybeans for 12 US Midwestern states using the EPIC (Environmental Policy Integrated Climate) model. Between 2008 and 2016, over 2 Mha of grassland were converted to crop production in these states, with much less cropland concomitantly abandoned or retired from production. The net change in grassland-cropland conversion increased annual soil erosion by 7.9%, nitrogen (N) loss by 3.7%, and soil organic carbon loss by 5.6% relative to that of existing cropland, despite an associated increase in cropland area of only 2.5%. Notably, the above estimates represent the scenario of converting unmanaged grassland to tilled corn and soybeans, and impacts varied depending upon crop type and tillage regime. Corn and soybeans are dominant biofuel feedstocks, yet the grassland conversion and subsequent environmental impacts simulated in this study are likely not attributable solely to biofuel-driven land use change since other factors also contribute to corn and soybean prices and land use decisions. Nevertheless, our results suggest grassland conversion in the Upper Midwest has resulted in substantial degradation of soil quality, with implications for air and water quality as well. Additional conservation measures are likely necessary to counterbalance the impacts, particularly in areas with high rates of grassland conversion (e.g., the Dakotas, southern Iowa).