Prostaglandin E2/Leukotriene B4 balance and viral load in distinct clinical stages of COVID-19: A cross-sectional study.

BACKGROUND: Prostaglandin E2 (PGE2) and leukotriene B4 (LTB4) are eicosanoids involved in modulation of the antiviral immune response. Recent studies have identified increased levels of several eicosanoids in the plasma and bronchoalveolar lavage of patients with coronavirus disease (COVID-19). This study investigated correlations between plasma levels of PGE2 and LTB4 and clinical severity of COVID-19. METHODS: This cross-sectional study involved non-infected (n = 10) individuals and COVID-19 patients classified as cured (n = 13), oligosymptomatic (n = 29), severe (n = 15) or deceased (n = 11). Levels of D-dimer a, known COVID-19 severity marker, PGE2 and LTB4 were measured by ELISAs and data were analysed with respect to viral load. RESULTS: PGE2 plasma levels were decreased in COVID-19 patients compared to the non-infected group. Changes in PGE2 and LTB4 levels did not correlate with any particular clinical presentations of COVID-19. However, LTB4 was related to decreased SARS-CoV-2 burden in patients, suggesting that only LTB4 is associated with control of viral load. CONCLUSIONS: Our data indicate that PGE2/LTB4 plasma levels are not associated with COVID-19 clinical severity. Hospitalized patients with COVID-19 are treated with corticosteroids, which may influence the observed eicosanoid imbalance. Additional analyses are required to fully understand the participation of PGE2 receptors in the pathophysiology of COVID-19.

Digitally managed larviciding as a cost-effective intervention for urban malaria: operational lessons from a pilot in São Tomé and Príncipe guided by the Zzapp system.

BACKGROUND: Once a mainstay of malaria elimination operations, larval source management (LSM)-namely, the treatment of mosquito breeding habitats-has been marginalized in Africa in favour of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS). However, the development of new technologies, and mosquitoes' growing resistance to insecticides used in LLINs and IRS raise renewed interest in LSM. METHODS: A digitally managed larviciding (DML) operation in three of the seven districts of São Tomé and Príncipe (STP) was launched by the Ministry of Health (MOH) and ZzappMalaria LTD. The operation was guided by the Zzapp system, consisting of a designated GPS-based mobile application and an online dashboard, which facilitates the detection, sampling and treatment of mosquito breeding sites. During the operation, quality assurance (QA) procedures and field management methods were developed and implemented. RESULTS: 12,788 water bodies were located and treated a total of 128,864 times. The reduction impact on mosquito population and on malaria incidence was 74.90% and 52.5%, respectively. The overall cost per person protected (PPP) was US$ 0.86. The cost varied between areas: US$ 0.44 PPP in the urban area, and US$ 1.41 PPP in the rural area. The main cost drivers were labour, transportation and larvicide material. CONCLUSION: DML can yield highly cost-effective results, especially in urban areas. Digital tools facilitate standardization of operations, implementation of QA procedures and monitoring of fieldworkers' performance. Digitally generated spatial data also have the potential to assist integrated vector management (IVM) operations. A randomized controlled trial (RCT) with a larger sample is needed to further substantiate findings.

An evidence-informed policymaking (EIPM) competency profile for the Brazilian Health System developed through consensus: process and outcomes.

BACKGROUND: Evidence-informed policymaking (EIPM) requires a set of individual and organizational knowledge, skills and attitudes that should be articulated with background factors and needs. In this regard, the development of an EIPM competency profile is important to support the diagnosis, planning and implementation of EIPM. PURPOSE: To present the process and outcomes of the development of an EIPM competency profile by an expert committee, to be applied in different contexts of the Brazilian Health System. METHODS: A committee of experts in EIPM shared different views, experiences and opinions to develop an EIPM competency profile for Brazil. In six consensus workshops mediated by facilitators, the committee defined from macro problems to key actions and performances essential for the competency profile. The development steps consisted of: (1) Constitution of the committee, including researchers, professionals with practical experience, managers, and educators; (2) Development of a rapid review on EIPM competency profiles; (3) Agreement on commitments and responsibilities in the processes; (4) Identification and definition of macro problems relating to the scope of the competency profile; and (5) Outlining of general and specific capacities, to be incorporated into the competency profile, categorized by key actions. RESULTS: The development of the EIPM competency profile was guided by the following macro problems: (1) lack of systematic and transparent decision-making processes in health policy management; (2) underdeveloped institutional capacity for knowledge management and translation; and (3) incipient use of scientific evidence in the formulation and implementation of health policies. A general framework of key actions and performances of the EIPM Competency Profile for Brazil was developed, including 42 specific and general key actions distributed by area of activity (Health Management, Scientific Research, Civil Society, Knowledge Translation, and Cross-sectional areas). CONCLUSIONS: The competency profile presented in this article can be used in different contexts as a key tool for the institutionalization of EIPM.

Temporomandibular trauma and reflections on personal evaluation.

The International Consortium Network/Orofacial Pain Special Interest Group focuses on temporomandibular disease diagnosis procedure guidelines as a reference iQAn this scope. Concerning this reference, the aim of this study was to comprehensively analyze injury and sequela frames within European and American approaches to personal damage. A quasiexperimental pilot study of Portuguese orofacial trauma cases in a medico-legal evaluation database was performed with an interrupted time series design. The clinical data were recorded following five criteria of TMJ diagnosis (jaw opening, pain, anatomical deficit, functional deficit, clinical sounds, and occlusal deficit) under three degrees of severity. The injury frame evaluation was recorded in the first-degree stage in all criteria. Pain, as a sequela, was the criterion present in 45% of the sample as spontaneous (20%) or stimulated (25%). Temporomandibular trauma damage evaluation emphasizes the accurate injury diagnosis and sequela framework. Orofacial trauma analysis should focus on the inclusion or exclusion of a TMD diagnosis. This study suggests revising the reference tables on personal damage, considering the inclusion of TMD and its categorization and impact.

Spectroscopic signatures of nonpolarons: the case of diamond.

Polarons are quasi-particles made from electrons interacting with vibrations in crystal lattices. They derive their name from the strong electron-vibration polar interactions in ionic systems, that induce spectroscopic and optical signatures of such quasi-particles. In this paper, we focus on diamond, a non-polar crystal with inversion symmetry which nevertheless shows interesting signatures stemming from electron-vibration interactions, better denoted "nonpolaron" signatures in this case. The (non)polaronic effects are produced by short-range crystal fields, while long-range quadrupoles only have a small influence. The corresponding many-body spectral function has a characteristic energy dependence, showing a plateau structure that is similar to but distinct from the satellites observed in the polar Fröhlich case. We determine the temperature-dependent spectral function of diamond by two methods: the standard Dyson-Migdal approach, which calculates electron-phonon interactions within the lowest-order expansion of the self-energy, and the cumulant expansion, which includes higher orders of electron-phonon interactions. The latter corrects the nonpolaron energies and broadening, providing a more realistic spectral function, which we examine in detail for both conduction and valence band edges.

Molecular data reveal multiple lineages of Scinax nebulosus (Spix, 1824) (Anura: Hylidae) with Plio-Pleistocene diversification in different Brazilian regions.

To understand the organism's history, we can start assessing the complexity of the biome where they occur. In this study, we used a region of the mitochondrial genome, the rRNA 16S, to evaluate the genetic differentiation in Scinax nebulosus along with its geographical range highlighting important Brazilian biomes as Restinga, Cerrado, Amazon, and Atlantic Forest. Geographically structured genetic divergence was observed within the species S. nebulosus. The values of the fixation index (Фst) and the pairwise Fst index were high and significant regarding this structuring. Besides, the haplotype network corroborates these results with the haplotypes arrangement found by separating the S. nebulosus populations in two major groups: North and Northeast. The lineage delimitation analyses indicate the occurrence of several lineages with divergence mainly between the samples from the Northeast group. Thus, we can suggest that S. nebulosus may present itself as a group of cryptic species due to the genetic characteristics found. The existence of a mosaic of heterogeneous habitats may explain the genetic divergence found, which justifies the existence of cryptic species in this group. However, this hypothesis needs more detail in molecular studies, including large sample sizes and other population and demographic analyses.

Histomorphometric analysis of implant osseointegration using hydrophilic implants in diabetic rats.

OBJECTIVES: To evaluate peri-implant bone formation of titanium implants using an in vivo rat model with and without uncontrolled diabetes mellitus (DM) to evaluate osseointegration of hydrophobic (Neoporos®) and hydrophilic (Acqua®) surfaces. MATERIALS AND METHODS: 54 rats were divided into two groups: DM group (DMG) (streptozotocin-induced diabetes) and a control group (CG). Implants with hydrophobic (Neoporos®) and hydrophilic surfaces (Acqua®) were placed in the left or right tibia of animals. Animals were further divided into three groups (n = 9) euthanized after 7, 14, or 28 days. Bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) were assessed in total, cortical, and medullary areas. RESULTS: The DMG group, after a 7-day healing period, yielded with the Acqua implants presented significantly higher total BIC (+37.9%; p=0.03) and trabecular BIC (%) (+46.3%; p=0.02) values in comparison to the Neoporos implants. After 28 days of healing, the CG yielded that the cortical BAFO of Acqua implants to be significantly, 14%, higher (p=0.04) than Neoporos implants. CONCLUSION: The positive effects of the Acqua surface were able to counteract the adverse impact of uncontrolled DM at early osseointegration periods. After 28 days in vivo, the metabolic systemic impairment caused by DM overcame the surface treatment effect, leading to impaired osseointegration in both hydrophilic and hydrophobic implants. CLINICAL RELEVANCE: The adverse effects of diabetes mellitus with respect to bone healing may be minimized by deploying implants with strategically modified surfaces. This study evaluated the effects of implants with Acqua® and Neoporos® surfaces in both diabetic and healthy animals. During the initial healing period in diabetic animals, the hydrophilic surface was demonstrated to have beneficial effect on osseointegration in comparison to the hydrophobic surface. The results provide an insight into early healing, but the authors suggest that a future short-term and long-term clinical study is needed to assess the possible benefit of the Acqua® implant as well as in increasing the predictability of implant osseointegration.

Analysis of the color matching of universal resin composites in anterior restorations.

OBJECTIVE: To evaluate color matching of universal composite restorations performed in anterior teeth using two evaluation methods. MATERIALS AND METHODS: Sixty class III preparations were made on denture central incisors with different shades (A1-A3) and restored with multishade (Tetric Evoceram, Filtek Universal, and TPH Spectra Universal) and single-shade (Omnichroma) universal composites (n = 5). For photographic analysis, a digital photograph of each specimen was taken under standardized set-up. Color measurements were taken in the center of the restoration, and in the tooth surface 1.0 mm adjacent from the tooth/restoration margin. CIELab coordinates were recorded and color difference analysis (ΔE) was made using the CIEDE-2000 formula. For visual analysis, calibrated observers performed visual scoring of color matching and differences were graded as 0:excellent match; 1:very good match; 2:not so good match; 3:obvious mismatch; 4:huge mismatch. All data were statistically analyzed using a linear mixed model analysis with a confidence interval of 95%. RESULTS: For photographic analysis, Omnichroma showed the highest ΔE compared to the other composites for all shades (P < .05), without difference among experimental groups regarding tooth shade. For visual analysis, Omnichroma showed the highest scores (P < .05) for all teeth shades, without differences between the other groups. Furthermore, there were no differences between visual scores for different shades of a same resin composite group. CONCLUSIONS: Multishade universal composites presented higher color matching than the single shade universal composite. There were no differences of color matching for different tooth shades for all composites. CLINICAL SIGNIFICANCE: Universal composites with increased color matching may be helpful to simplify anterior restorations, minimizing clinical errors.

Type 1 diabetes in children is not a predisposing factor for oral yeast colonization.

Type 1 diabetes mellitus (T1D) is considered a risk factor associated with oral yeast infections. The aim of this study was to evaluate the yeast oral carriage (in saliva and mucosal surface) of children with T1D and potential relation with host factors, particularly the subset of CD4+ T cells. Yeasts were quantified and identified in stimulated saliva and in cheek mucosal swabs of 133 diabetic T1D and 72 healthy control subjects. Salivary lymphocytes were quantified using flow cytometry. The presence of yeasts in the oral cavity (60% of total patients) was not affected by diabetes, metabolic control, duration of the disease, salivary flow rate or saliva buffer capacity, by age, sex, place of residence, number of daily meals, consumption of sweets or frequency of tooth brushing. Candida albicans was the most prevalent yeast species, but a higher number of yeast species was isolated in nondiabetics. T1D children with HbA1c ≤ 7.5 (metabolically controlled) presented higher number of CD4+ T salivary subsets when compared with the other groups of children (non-diabetic and nonmetabolically controlled) and also presented the highest number of individuals without oral yeast colonization. In conclusion, T1D does not predisposes for increased oral yeast colonization and a higher number of salivary CD4+T cells seems to result in the absence of oral colonization by yeasts.

Long-Term Follow Up After Successful Percutaneous Balloon Mitral Valvuloplasty.

BACKGROUND: Percutaneous balloon mitral valvuloplasty (PMV) is the cornerstone of rheumatic mitral stenosis treatment in suitable patients. Previous studies have reported low rates of technical failure and few major complications, with good long-term results after successful PMV. The study aim was to assess the very long-term outcome in patients after PMV performed at a single tertiary center. METHODS: Between 1991 and 2010, a total of 213 consecutive patients underwent PMV at the authors' center. The criteria used to define successful procedure were post-procedural mitral valve area ≥1.5 cm2 and mitral regurgitation less than grade III, without in-hospital major cardiac or cerebrovascular events. The primary endpoint evaluated during the follow up period was the occurrence of cardiovascular death and need for mitral reintervention (percutaneous or surgical). Kaplan-Meier curves were generated to determine event rates, and predictors of major cardiac events in patients with successful PMV were determined using Cox regression analysis. RESULTS: A total of 190 patients (89%) underwent a successful PMV; 88% of these are currently being followed up at the authors' center. During a mean follow up of 11.2 ± 7.3 years, at least one major adverse cardiac event occurred in 25.1% of patients (6.6% all-cause death, 6.6% repeated PMV, 21% required mitral valve surgery). Cumulative event-free survival at 20 years was 54.7 ± 6.3%. On univariate analysis, the echocardiographic score [hazard ratio (HR) = 1.25 (1.00-1.70), p <0.05], left atrial diameter [HR = 1.06 (1.01-1.11), p <0.05] and mean mitral valve gradient soon after the procedure [HR = 1.25 (1.02-1.55), p <0.05] were predictors of events. On multivariate analysis, the echocardiographic mitral valve score before PMV was the only independent predictor of primary outcome [HR=1.75 (1.16-2.64), p<0.01]. CONCLUSIONS: Up to 20 years after successful PMV, a sizeable proportion of patients remained event-free, which confirmed the late efficacy of PMV. Among the present patient cohort, echocardiographic score before PMV was the only independent predictor of long term events.

Bicuspid aortic valve outcomes.

BACKGROUND: Bicuspid aortic valve is the most common CHD. Its association with early valvular dysfunction, endocarditis, thoracic aorta dilatation, and aortic dissection is well established. OBJECTIVE: The aim of this study was to assess the incidence and predictors of cardiac events in adults with bicuspid aortic valve. METHODS: We carried out a retrospective analysis of cardiac outcomes in ambulatory adults with bicuspid aortic valve followed-up in a tertiary hospital centre. Outcomes were defined as follows: interventional - intervention on the aortic valve or thoracic aorta; medical - death, aortic dissection, aortic valve endocarditis, congestive heart failure, arrhythmias, or ischaemic heart disease requiring hospital admission; and a composite end point of both. Kaplan-Meier curves were generated to determine event rates, and predictors of cardiac events were determined by multivariate analysis. RESULTS: A total of 227 patients were followed-up over 13±9 years; 29% of patients developed severe aortic valve dysfunction and 12.3% reached ascending thoracic aorta dimensions above 45 mm. At least one cardiac outcome occurred in 38.8% of patients, with an incidence rate at 20 years of follow-up of 47±4%; 33% of patients were submitted to an aortic valve or thoracic aorta intervention. Survival 20 years after diagnosis was 94±2%. Independent predictors of the composite end point were baseline moderate-severe aortic valve dysfunction (hazard ratio, 3.19; 95% confidence interval, 1.35-7.54; p<0.01) and aortic valve leaflets calcification (hazard ratio, 4.72; 95% confidence interval, 1.91-11.64; p<0.005). CONCLUSIONS: In this study of bicuspid aortic valve, the long-term survival was excellent but with occurrence of frequent cardiovascular events. Baseline aortic valve calcification and dysfunction were the only independent predictors of events.

Contribution of Dobutamine Stress Echocardiography to the Diagnosis and Prognosis of Low-Flow/Low-Gradient Aortic Stenosis.

BACKGROUND: Aortic valve replacement (AVR) is the treatment of choice in patients with severe symptomatic aortic stenosis (AS). Patients with a low left ventricular ejection fraction (LVEF) represent a challenge for evaluation and therapeutic decision. Dobutamine stress echocardiography (DSE) allows the distinction to be made between fixed low-flow/low-gradient (LF/LG) AS and pseudosevere AS. METHODS: Between 2001 and 2014 a retrospective analysis was conducted of patients who underwent DSE to investigate severe AS. DSE was performed in 3- to 5-min steps up to a maximum dose of 20 µg/kg/min. Parameters evaluated at baseline and at each step of DSE included: left ventricular enddiastolic volume (LVEDV) and left ventricular endsystolic volume (LVESV), maximum gradient (MaxG), mean gradient (MG) and aortic valve area (AVA). AS was considered to be severe if the AVA at peak dose was ≤1 cm2. Patients were allocated to two groups according to their therapy: group 1 received only medical treatment, while group 2 underwent AVR. The average follow up was 51.5 ± 4.4 months. RESULTS: A total of 41 patients (28 males, 13 females; mean age 71.7 ± 8.3 years) was analyzed. Severe AS was diagnosed in 34 patients (83%). Baseline echocardiographic characteristics were: AVA 0.7 ± 0.2 cm2, MaxG 42.0 ± 9.1 mmHg, MG 25.6 ± 6.4 mmHg, LVEF 33.1 ± 8.4%, LVEDV 149.6 ± 44.5 ml, and LVESV 104.0 ± 42.6 ml. At peak DSE, AVA was 0.8 ± 0.2 cm2, MaxG 62.7 ± 18.2 mmHg, MG 38.1 ± 11.6 mmHg, LVEF 42.2 ± 9.9%, LVEDV 142.6 ± 43.85 ml, and LVESV 89.7 ± 37.4 ml. Nineteen patients were allocated to group 1, and 22 to group 2. In group 2, two patients underwent transcatheter aortic valve implantation (TAVI) and 20 had surgery. Mortality in group 1 was significantly higher than in group 2 (78.9% versus 27.3%). A Cox proportional hazard model analysis showed that no-intervention was the only predictor of mortality (unadjusted to age; hazard ratio (HR) 5.13, 95% confidence interval (CI) 1.96-13.44, p = 0.001; adjusted to age - HR 4.01, 95% CI 1.46-11.01, p = 0.007). CONCLUSIONS: LF/LG AS has a poor prognosis without intervention. DSE allows the lesion severity to be established. In the present study intervention was a predictor of survival during follow up.

Machine learning methods, applications and economic analysis to predict heart failure hospitalisation risk: a scoping review protocol.

INTRODUCTION: Machine learning (ML) has emerged as a powerful tool for uncovering patterns and generating new information. In cardiology, it has shown promising results in predictive outcomes risk assessment of heart failure (HF) patients, a chronic condition affecting over 64 million individuals globally.This scoping review aims to synthesise the evidence on ML methods, applications and economic analysis to predict the HF hospitalisation risk. METHODS AND ANALYSIS: This scoping review will use the approach described by Arksey and O'Malley. This protocol will use the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) Protocol, and the PRISMA extension for scoping reviews will be used to present the results. PubMed, Scopus and Web of Science are the databases that will be searched. Two reviewers will independently screen the full-text studies for inclusion and extract the data. All the studies focusing on ML models to predict the risk of hospitalisation from HF adult patients will be included. ETHICS AND DISSEMINATION: Ethical approval is not required for this review. The dissemination strategy includes peer-reviewed publications, conference presentations and dissemination to relevant stakeholders.

Esophageal Perforation by Fish Bone Ingestion Causing Purulent Pericarditis.

A previously healthy 38-year-old woman presented with new-onset sudden chest pain radiating to the back, associated with cough, dyspnea, nausea, vomiting, and gastric fullness after eating a bony fish. A diagnosis of gastroesophageal reflux disease was made. After a week of progressive worsening of her symptoms, she was referred to the specialist hospital. There, computed tomography imaging strongly suggested that a likely fishbone had penetrated the esophagus into the mediastinal structures; it seemed to have produced a pneumopericardium. Other tests suggested diffuse changes in ventricular repolarization, pericardial thickening, and diastolic restriction. Exploratory thoracotomy confirmed esophageal-pericardial perforation by the fishbone and purulent pericarditis. Despite appropriate surgical repair, the patient died on fifth postoperative day from an asystolic cardiac arrest that was refractory to repeated attempts to resuscitate her.

Challenges and Management of Capillary Intraosseous Hemangioma in the Mandibular Symphysis: A Case Report.

Capillary intraosseous hemangioma is a benign vascular neoplasm that affects bone tissue, yet its occurrence in the jaw bones has been seldom reported in the literature. We present a case of a capillary intraosseous hemangioma located in the mandibular symphysis of a 28-year-old male. Initially addressed by the patient's dentist as an infectious lesion of endodontic origin, the sudden worsening of the condition, marked by the development of a rapidly expanding exophytic mandibular lesion and tooth mobility, led to the consideration of various potential diagnoses. Subsequently, an incisional biopsy was performed, triggering multiple episodes of recurrent bleeding, leading to several visits to the emergency department, and prompting an urgent status upgrade for the patient. Upon the histological diagnosis of vascular neoplasm, the patient underwent the excision of the lesion, with a favorable and uneventful evolution, although with expected sequelae. As a result, a temporary prosthetic solution, comprising a Maryland Bridge, was implemented, with plans for guided bone regeneration and implant-supported fixed dental prostheses currently in progress. This case underscores the diagnostic and therapeutic challenges associated with this rare condition. Consequently, achieving the optimal outcome for the patient largely depends on a multidisciplinary approach, emphasizing the critical importance of thorough preoperative assessment, along with a well-devised treatment plan and rapid intervention.

Oral Gastric Heterotopia: First Reported Case in the Hard Palate.

Gastric heterotopia is characterized by the presence of mature gastric tissue outside the stomach, yet its occurrence in the palate has not been previously documented. We describe a case of gastric heterotopia in the hard palate of an elderly female patient, presenting as a swollen mass with associated secretion. Given the patient's age and clinical symptoms, a presumptive diagnosis of a malignant tumor originating from the minor salivary glands was made. An incisional biopsy of the mass revealed gastric heterotopia. Subsequently, the extended excision of the lesion was performed, leading to the full resolution of the patient's symptoms. After a two-year follow-up period, no evidence of recurrence was observed. The importance of this case, underscored by the unprecedented location of gastric heterotopia, emphasizes the critical need for thorough evaluation to avert misdiagnosis, as well as the complete surgical excision of the lesion to prevent recurrence.

Orofacial assessment as digital path for forensic and legal evidence record.

In forensic scenarios, such as armed conflicts or mass disasters, the oral cavity can be a valuable source of identification information relevant to legal issues. In many European Union countries, it is mandatory to register dental records for identification purposes. A pilot and quasi-experimental study was performed. The study aims to analyze two methodologies, photography and wireless intraoral (IO) laser scanner, in the scope of the orofacial record in forensic pathology, highlighting their impact on human identification. The IO scanner i700 (Medit, Lusobionic, Portugal) and Canon 5D-Full Frame equipment were used to record the individual status, living patients (n = 5), and forensic cases (n = 5). IO and extraoral anatomical structures were recorded following six parameters: time, mineralized and soft detail, communication, extra devices, and distortion. The statistical analysis was performed in accordance with a scoring system and Mann-Whitney (P < 0.05) analysis. The photography method recorded extraoral data for all samples (score range between 15 and 23). The time elapsed to complete an IO scan in forensic cases was shorter than with photography, without requiring additional sources of light or mirror devices. Living patients and corpses identified statistically significant differences. It can be concluded that laser scanners are a valuable tool in the field of forensic pathology and can be used to record and analyze anatomic-morphological data for identification purposes accurately. Key points: Human identification engages in orofacial details records.Photographic and laser scans record intraoral and extraoral anatomic structures.Forensic cases assessed by intraoral scanner technology are accurate and less time-consuming, optimizing the orofacial data for identification.

Short curing time bulk fill composite systems: volumetric shrinkage, degree of conversion and Vickers hardness.

This study aimed to evaluate volumetric polymerization shrinkage, degree of conversion and Vickers hardness of four bulk-fill resin composites light-activated with their dedicated light curing units (LCUs). Four groups were evaluated, according to the type of composite and curing mode: Tetric EvoCeram Bulk-fill (TEBO) and Tetric EvoFlow Bulk-fill (TEBF) were light-activated with Bluephase Style 20i (20s, in high-mode), while Tetric Powerfill (TEPO) and Tetric Powerflow (TEPF) were light-activated with Bluephase PowerCure (3s). Volumetric polymerization shrinkage test (n = 6) was performed in standardized box-shaped class-I cavities of extracted third molars (4 x 4 x 4 mm). Teeth were scanned before and after resin composite application by micro-computed tomography, and acquired data were evaluated with Amira software. Degree of conversion (n = 5) was evaluated at the top and bottom surfaces of composite cylindric samples (4 mm diameter, 4 mm thickness) using an FT-IR spectrometer (spectra between 1,500 and 1,800 cm-1, 40 scans at a resolution of 4 cm-1). Three Vickers indentations (50 g / 15 s), spaced 500 µm apart, were performed on the top and bottom composite surfaces and averaged. One-way ANOVA was used for data evaluation. TEPF showed the lowest volumetric polymerization shrinkage (p < 0.05), while the other composites were not significantly different within each other (p > 0.05). All materials presented a significant decrease in degree of conversion and Vickers hardness when compared top to bottom surfaces (p < 0.05). Bottom to top surface ratios for degree of conversion ranged from 0.8 (TEBO and TEPO) to 0.9 (TEBF and TEPF), and from 0.4 (TEPO) to 0.7 (TEBF and TEPF) for hardness. In conclusion, resinous materials present a decrease in hardness and degree of conversion from top to bottom even when a higher power is used, while the flowable material TEPF showed the lowest volumetric shrinkage values compared to the other materials.

Analysis of translucency parameter and fluorescence intensity of 5 resin composite systems.

The natural outcome of dental composite restorations highly depends on the translucency of the enamel layer and fluorescence. This study aimed to evaluate the Translucency Parameter (TP) and Fluorescence Intensity (FI) of five different resin composite systems. Seven discs of each composite brand were prepared in a circular increasing thickness. For TP, a spectrophotometer measured the samples' colors. The color difference within the white/black backgrounds obtained the translucency parameter. For FI, samples were exposed to UV light, and ten photographs per group were taken. Each specimen was analyzed digitally. A mixed model analysis to a 95% confidence level analyzed groups differences. Higher values of TP were observed for ED and EL, followed by FZ. The lowest values were observed for EO and FO. FI values descending order was EL>FO>EO>ED>FZ. The composition of fillers and organic matrix influenced the behavior of fluorescence and translucency of resin composites. Key words:Resin composite, fluorescence, color, translucency parameter.

Giant pericardial cyst mimicking dextrocardia on chest X-ray.

Pericardial cysts are rare benign congenital malformations, usually small, asymptomatic and detected incidentally on chest X-ray as a mass located in the right costophrenic angle. Giant pericardial cysts are very uncommon and produce symptoms by compressing adjacent structures. In this report, the authors present a case of a symptomatic giant pericardial cyst incorrectly diagnosed as dextrocardia on chest X-ray.