Differential pulmonary in vitro toxicity of two small-sized polyvinylpyrrolidone-coated silver nanoparticles.

Silver nanoparticles (AgNP), with their important properties, are being used in a range of sectors from industry to medicine, leading to increased human exposure. Hence, their toxicity potential needs to be comprehensively evaluated. It was postulated that within small-sized (≤20 nm) polyvinylpyrrolidone-coated silver nanoparticles (PVP-AgNP), minor size differences may significantly induce different toxicity profiles and involve varying cellular pathways. Therefore, the aim of this study was to examine the influence of differing size AgNP with 10 nm (AgNP10) and 20 nm (AgNP20) (up to 100 µg/ml), as well as to ionic silver as AgNO3 for 24 and 48 h, using the human lung cell line A549. The effects on cell viability, proliferation, apoptosis, DNA damage and cell cycle dynamics were assessed. Results for both time periods showed that for low concentrations (<5 µg/ml), AgNP20 were more cytotoxic than AgNP10, however, at higher doses, AgNP10 exhibited higher toxicity. For concentrations >50 µg/ml, AgNP10 induced severe DNA damage (comet class 3-4), cell cycle arrest at G2 phase and late-stage apoptosis, while AgNP20 induced cell cycle arrest at S phase and an increase in the percentage sub-G1, which did not recover after 48 h, and late-stage apoptosis/necrosis. In longer-term exposures, the greater impairment in colony formation due to AgNP exposure than to silver ion supports that nanotoxicity is not exclusively due to the released ion. Data suggest that toxicity mediated by small AgNP (≤20 nm) in lung cells is not only dependent on the level of particle internalization, but also on AgNP size and concentration, which may involve varying pathways as targets.

Coating independent cytotoxicity of citrate- and PEG-coated silver nanoparticles on a human hepatoma cell line.

The antibacterial potential of silver nanoparticles (AgNPs) resulted in their increasing incorporation into consumer, industrial and biomedical products. Therefore, human and environmental exposure to AgNPs (either as an engineered product or a contaminant) supports the emergent research on the features conferring them different toxicity profiles. In this study, 30nm AgNPs coated with citrate or poly(ethylene glycol) (PEG) were used to assess the influence of coating on the effects produced on a human hepatoma cell line (HepG2), namely in terms of viability, apoptosis, apoptotic related genes, cell cycle and cyclins gene expression. Both types of coated AgNPs decreased cell proliferation and viability with a similar toxicity profile. At the concentrations used (11 and 5µg/mL corresponding to IC50 and ~IC10 levels, respectively) the amount of cells undergoing apoptosis was not significant and the apoptotic related genes BCL2 (anti-apoptotic gene) and BAX (pro-apoptotic gene) were both downregulated. Moreover, both AgNPs affected HepG2 cell cycle progression at the higher concentration (11µg/mL) by increasing the percentage of cells in S (synthesis phase) and G2 (Gap 2 phase) phases. Considering the cell-cycle related genes, the expression of cyclin B1 and cyclin E1 genes were decreased. Thus, this work has shown that citrate- and PEG-coated AgNPs impact on HepG2 apoptotic gene expression, cell cycle dynamics and cyclin regulation in a similar way. More research is needed to determine the properties that confer AgNPs at lower toxicity, since their use has proved helpful in several industrial and biomedical contexts.

Effect of four different mono and multi-wave light-curing units on the Knoop hardness of veneer resin composites.

OBJECTIVES: To evaluate the effect of mono and multi-wave light-curing units (LCUs) on the Knoop hardness of resin-based composites (RBC) that use different photoinitiators. METHODS: Central incisor-shaped specimens 12 mm long, 9 mm wide, and 1.5 mm thick were made from 2 RBCs that use different photoinitiators: Tetric N-Ceram (Ivoclar Vivadent) - and Vittra APS (FGM), both A2E shade. They were light-cured with 4 different LCUs: two claimed to be multi-wave - VALO Grand (Ultradent) and Emitter Now Duo (Schuster); and two were monowave - Radii Xpert (SDI) and Elipar DeepCure-L (3 M Oral Care) using 2 different light exposure protocols: one 40 s exposure centered over the specimen; and two 20 s light exposures that delivered light from two positions to better cover the entire tooth. 16 groups with 10 specimens in each group were made. The Knoop hardness (KH, kg/mm2) was measured at the top and bottom of the specimen in the center and at the cervical, incisal, mesial, and distal peripheral regions. The active tip diameters (mm) and spectral radiant powers (mW/nm) of the LCUs were measured with and without the interposition of the RBC, as well as the radiant exposure beam profiles (J/cm²) delivered to the top of the RBCs. The data was analyzed using Three-way ANOVA and Tukey's tests (α = 0.05). RESULTS: The VALO Grand (1029 mW) emitted twice the power of the Radii Xpert (500 mW). The KH values of VI and TN resin composite specimens were significantly affected by the LCU used (p < .001), the measurement location (p < .001), and the surface of the specimen (p < .001). LCUs with wider tip diameters produced greater Knoop hardness values at the peripheries of the 12 mm of long, 9 mm wide specimens. In general, the VALO Grand produced the highest KH values, followed by Elipar DeepCure-L, then by Radii Xpert. The Emitter Now Duo LCU produced the lowest values. Exposing the veneers from two locations reduced the differences between the LCUs and the effect of the measurement location. Only the VALO Grand could fully cover the composite veneer with light when the two locations were used. SIGNIFICANCE: The light tip must cover the entire restoration to photocure the RBC beneath the light tip.

Hydrogel Bioinks of Alginate and Curcumin-Loaded Cellulose Ester-Based Particles for the Biofabrication of Drug-Releasing Living Tissue Analogs.

3D bioprinting is a versatile technique that allows the fabrication of living tissue analogs through the layer-by-layer deposition of cell-laden biomaterials, viz. bioinks. In this work, composite alginate hydrogel-based bioinks reinforced with curcumin-loaded particles of cellulose esters (CEpCUR) and laden with human keratinocytes (HaCaT) are developed. The addition of the CEpCUR particles, with sizes of 740 ± 147 nm, improves the rheological properties of the inks, increasing their shear stress and viscosity, while preserving the recovery rate and the mechanical and viscoelastic properties of the resulting fully cross-linked hydrogels. Moreover, the presence of these particles reduces the degradation rate of the hydrogels from 26.3 ± 0.8% (ALG) to 18.7 ± 1.3% (ALG:CEpCUR_10%) after 3 days in the culture medium. The 3D structures printed with the ALG:CEpCUR inks reveal increased printing definition and the ability to release curcumin (with nearly 70% of cumulative release after 24 h in PBS). After being laden with HaCaT cells (1.2 × 106 cells mL-1), the ALG:CEpCUR bioinks can be successfully 3D bioprinted, and the obtained living constructs show good dimensional stability and high cell viabilities at 7 days post-bioprinting (nearly 90%), confirming their great potential for application in fields like wound healing.

Survival of severely compromised endodontically treated teeth restored with or without a fiber glass post.

OBJECTIVE: The use of a fiber glass post (FGP) type and choice of FGP diameter to restore endodontically treated incisors without ferrule is controversial. This study evaluated survival rate and failure mode of severely compromised central incisors without ferrule rehabilitated using resin-based composite (RBC) with or without FGP with different diameters. METHODOLOGY: A total of 60 decoronated bovine incisors without a ferrule were endodontically treated and prepared for 1.4, 1.6, and 1.8 mm diameter FGPs (Whitepost System DC 0.5, Fit 0.4, and DCE 0.5; FGM). Half of the teeth received FGPs cemented using dual-cure resin cement (Allcem Core; FGM), the other half were filled using only bulk-fill RBC (OPUS Bulk Fill; FGM). The crowns were directly restored with RBC. The roots were embedded in polystyrene resin and the periodontal ligament was simulated with polyether impression material. Fatigue testing was conducted under 5 Hz cyclic loading at 30 degrees to the incisal edge, beginning at 50 N (5,000 cycles) as a warmup. After, the load was increased 100 N every 15,000 cycles until fracture occurred. All specimens were subjected to transillumination, micro-CT analysis, and digital radiography before and after fatigue testing. Fracture mode was classified according to severity and repair potential. Data were analyzed with Kaplan-Meier survival test and post hoc log-rank test (α=0.05) for pairwise comparisons. RESULTS: Using FGP significantly increased the number of cycles to failure, irrespective of FGP diameters (p=0.001). The FGP diameters had no statistically significant effect on cycles to failure or failure mode. CONCLUSION: Using FGP without ferrule improved survival rate of structurally severely compromised central incisors compared with rehabilitation without FGP. The diameter of the FGPs had no effect on the survival rate and failure mode.

Nanofibrillated cellulose/gellan gum hydrogel-based bioinks for 3D bioprinting of skin cells.

The development of suitable bioinks is an important research topic in the field of three-dimensional (3D) bioprinting. Herein, novel hydrogel-based bioinks composed of nanofibrillated cellulose (NFC) and gellan gum (GG) in different NFC/GG mass proportions (90:10, 80:20, 70:30, and 60:40) were developed and characterized. The increase in the content of GG, as well as its combination with NFC, enhanced their rheological properties, increasing both storage (G') and loss (G") moduli and the G' recovery capacity of the hydrogels (from 70.05 ± 3.06 % (90:10) to 82.63 ± 1.21 % (60:40)), as well as their mechanical properties, increasing the compressive stiffness and stress from 114.02 ± 10.93 Pa (90:10) to 337.16 ± 34.03 Pa (60:40) and from 18.27 ± 1.32 kPa (90:10) to 47.17 ± 3.59 kPa (60:40), respectively. The hydrogels were non-cytotoxic against human keratinocyte cells (HaCaT), with cell viabilities above 70 % for up to 72 h. The hydrogel 60:40 was loaded with HaCaT cells (3 × 106 cells mL-1) and bioprinted. The cell viability was maintained elevated until day 7 (90 ± 3 %) after bioprinting. These results highlight that the combination of these two biopolymers was a good strategy for the development of novel hydrogel-based bioinks for extrusion 3D bioprinting applications.

Effect of pre-heating methods and devices on the mechanical properties, post-gel shrinkage, and shrinkage stress of bulk-fill materials.

This study evaluated the effect of using two different pre-heating methods on the three resin-based composite (RBCs). Three paste viscosity bulk-fill RBCs (VisCalor Bulk [VC]; VOCO; x-tra fil Caps [XF], VOCO; Filtek One Bulk Fill [FO], 3 M) were pre-heated using either a VisCalor Dispenser (VOCO) to 65 °C, or the Caps Warmer (VOCO) to 37 °C, 54 °C, or 68 °C. The temperature inside the capsules and cavity was monitored before and after insertion into the matrix. Within 30 s of inserting the RBC, they were light-activated using a VALO (Ultradent) curing light for 20 s. The post-gel shrinkage (Shr - %), Flexural Strength (FS - MPa), Elastic Modulus (E - MPa), degree of conversion (DC - %), Knoop Hardness (KH - N/mm2), diametral tensile strength (DTS - MPa), and compressive strength (CS - MPa) of the RBCs were measured (10 specimens per group). The shrinkage stress was calculated using three-dimensional finite element analysis. Data were analyzed using one-way, two-way ANOVA and Tukey's test (α = 0.05). The temperature fell rapidly after the RBC was inserted into the cavity. Pre-heating the RBCs did not affect the mechanical properties. FO had the lowest E, DC, and KH values, VC had intermediate values, and XF achieved the highest values. The DTS and CS values were not affected by the various pre-heating methods, the temperature, or RBC. Pre-heating methods at 37 °C produced higher shrinkage for all RBCs. VC pre-heated to 65 °C produced the lowest stress when measured at 10 min after light activation.

Cytotoxicity of Nucleotide-Stabilized Graphene Dispersions on Osteosarcoma and Healthy Cells: On the Way to Safe Theranostics Agents.

An appealing strategy that overcomes the hydrophobicity of pristine graphene and favors its interaction with biological media is colloidal stabilization in aqueous medium with the support of a biomolecule, such as flavin mononucleotide (FMN), as exfoliating/dispersing agent. However, to establish FMN-stabilized graphene (PG-FMN) as suitable for use in biomedicine, its biocompatibility must be proved by a complete assessment of cytotoxicity at the cellular level. Furthermore, if PG-FMN is to be proposed as a theranostic agent, such a study should include both healthy and tumoral cells and its outcome should reveal the nanomaterial as selectively toxic to the latter. Here, we provide an in-depth comparative in vitro analysis of the response of Saos-2 human sarcoma osteoblasts (model tumor cells) and MC3T3-E1 murine preosteoblasts (undifferentiated healthy cells) upon incubation with different concentrations (10-50 µg mL-1) of PG-FMN dispersions constituted by flakes with different average lateral size (90 and 270 nm). Specifically, the impact of PG-FMN on the viability and cell proliferation, reactive oxygen species (ROS) production, and the cellular incorporation process, cell-cycle progression, and apoptosis has been evaluated. PG-FMN was found to be toxic to both types of cells by increasing ROS production and triggering cell-cycle arrest. The present results constitute a cautionary tale on the need to establish the effect of a nanomaterial not only on tumor cells but also on healthy ones before proposing it as anticancer agent.

Lack of plasma albumin impairs intravascular lipolysis and explains the associated free fatty acids deficiency and hypertriglyceridemia.

BACKGROUND: Abnormalities in lipid metabolism and transport are hallmarks in analbuminemic Nagase rats (NAR) and humans. Triglyceridemia is nearly 3- to 5-fold higher in female NAR than in control Sprague-Dawley rats (SDR). Also, NAR present with a severe plasma free fatty acid (FFA) deficit. There are conflicting results regarding the mechanisms underlying NAR hypertriglyceridemia. OBJECTIVE: We aimed at investigating whether liver lipogenesis and triglyceride secretion rates into the plasma contribute to the hypertriglyceridemia in NAR. We also studied whether heparin or albumin administration would release the hypothesized lipolysis inhibition in NAR. METHODS: The incorporation of tritiated water into lipids and the linear accumulation rate of plasma triglycerides after Triton WR1339 injection were the measures of liver lipogenesis and triglyceride secretion rates. RESULTS: Lipogenesis (596 ± 40 vs. 929 ± 124 µmol 3H2O/g/h) and triglyceride (4.25 ± 1.00 vs. 7.04 ± 1.68 mg/dL/min) secretion rates were slower (P ≤ 0.05) in fasted NAR than in control SDR. The injection of either heparin or albumin elicited an increase in NAR plasma FFA levels over time. FFA levels reached control levels 90 min after the albumin administration, increasing from 0.36 ± 0.05 to 1.34 ± 0.16 mEq/L (P ≤ 0.05). These results indicate that the lack of plasma albumin inhibits intravascular lipolysis and causes the FFA deficit observed in NAR. CONCLUSION: NAR hepatic triglyceride synthesis and output do not contribute to NAR hypertriglyceridemia. We propose that the lack of albumin diminishes intravascular lipolysis which reduces the plasma triglyceride removal rate and explain both NAR hypertriglyceridemia and FFA deficiency.

The role of letter features on the consonant-bias effect: Evidence from masked priming.

Recent research has shown an advantage of consonants at early stages of visual word recognition (C-bias), although the locus of this effect remains elusive. Here we examine whether the C-bias is affected by the consonant letters' features. Skilled readers performed a masked priming lexical decision task in which target words containing only either consonants without any ascending/descending features (flat words, canino[canine]) or consonants with ascending/descending features (non-flat words, palito[toothpick]) were preceded by briefly (50 ms) presented primes that could preserve the same consonants of the targets (cenune-CANINO, pelute-PALITO), the same vowels of the targets (raxizo-CANINO, fajibo-PALITO), or, as controls, unrelated (ruxuze-CANINO, fejube-PALITO) and identity primes (canino-CANINO, palito-PALITO). The case in which prime-target pairs were presented was also manipulated (lower-upper vs. upper-lower). Results showed that in both case conditions flat words were recognized faster than non-flat words. Evidence for the C-bias was observed both for flat and non-flat words in the lower-upper condition, in which a vowel inhibitory priming effect was also observed for non-flat words. In the upper-lower condition, however, the C-bias was restricted to flat words. These findings suggest that letter features play a role in the C-bias and ask for amendments in current models of visual word recognition.

Biocompatible chitosan-based composites with properties suitable for hyperthermia therapy.

Sustainably made, flexible and biocompatible composites, having environmentally friendly compositions and multifunctional capabilities, are promising materials for several emerging biomedical applications. Here, the development of flexible and multifunctional chitosan-based bionanocomposites with a mixed reduced graphene oxide-iron oxide (rGO-Fe3-xO4) filler is described. The filler is prepared by one-pot synthesis, ensuring good dispersibility of the Fe3-xO4 nanoparticles and rGO within the chitosan matrix during solvent casting. The resulting bionanocomposites present superparamagnetic response at room temperature. The antioxidant activity is 9 times higher than that of pristine chitosan. The mechanical properties of the films can be tuned from elastic (∼8 MPa) chitosan films to stiff (∼285 MPa) bionanocomposite films with 50% filler. The magnetic hyperthermia tests showed a temperature increase of 40 °C in 45 s for the 50% rGO-Fe3-xO4 film. Furthermore, the composites have no cytotoxicity to the nontumorigenic (HaCat) cell line, which confirms their biocompatibility and highlights the potential of these materials for biomedical applications, such as hyperthermia treatments.

Nanocellulose-based antifungal nanocomposites against the polymorphic fungus Candida albicans.

The design of functional materials capable of fighting fungal infections is of paramount importance given the intricate problem of multidrug-resistant pathogenic fungi. Herein, nanocomposites consisting of cross-linked poly([2-(methacryloyloxy)ethyl]trimethylammonium chloride) (PMETAC) and bacterial nanocellulose (BNC) were prepared, characterized and tested towards the polymorphic fungus Candida albicans. The BNC three-dimensional network enabled the in-situ polymerization of the non-toxic and bioactive quaternary-ammonium monomer, which originated transparent nanocomposites containing 10 and 40 wt.% of cross-linked PMETAC. Furthermore, the nanocomposites exhibit UV-A and UV-B blocking properties, high water-uptake capacity, thermal stability up to 200 °C, good viscoelastic (storage modulus > 1.7 GPa) and mechanical (Young's modulus ≥2.4 GPa) properties and are non-cytotoxic to human keratinocytes (HaCaT cells). The fungal inactivation reached a 4.4 ± 0.14-log CFU reduction for the nanocomposite containing only 10 wt.% of cross-linked PMETAC. Hence, these bioactive and non-cytotoxic materials can constitute potentially effective systems for the treatment of C. albicans infections.

Application of computed tomography for supernumerary teeth location in pediatric dentistry.

Conventional radiographs provide bi-dimensional images of three-dimensional structures limiting optimal treatment planning. To overcome this deficiency, Computed Tomography (CT) has been used as a diagnostic method in Medicine and Dentistry. CT allows for supernumerary teeth location, the establishment of positional relations with other teeth, and the assessment of surrounding bone thickness; thus, facilitating surgical access and technique choice while reducing the procedure time, of great importance in pediatric dental care. The aim of this study was to present the possibility of applying CT for supernumerary teeth location, through the case report of a five-year-old female patient presenting two supernumerary teeth in the anterior palatal area. In conclusion, CT appears to be an excellent image diagnostic method for locating unerupted supernumerary teeth, providing precise information for planning and performing the surgical approach, while reducing operatory time and post-operatory complications; factors of extreme importance when treating young children.

Survival of severely compromised endodontically treated teeth restored with or without a fiber glass post

Abstract Objective The use of a fiber glass post (FGP) type and choice of FGP diameter to restore endodontically treated incisors without ferrule is controversial. This study evaluated survival rate and failure mode of severely compromised central incisors without ferrule rehabilitated using resin-based composite (RBC) with or without FGP with different diameters. Methodology A total of 60 decoronated bovine incisors without a ferrule were endodontically treated and prepared for 1.4, 1.6, and 1.8 mm diameter FGPs (Whitepost System DC 0.5, Fit 0.4, and DCE 0.5; FGM). Half of the teeth received FGPs cemented using dual-cure resin cement (Allcem Core; FGM), the other half were filled using only bulk-fill RBC (OPUS Bulk Fill; FGM). The crowns were directly restored with RBC. The roots were embedded in polystyrene resin and the periodontal ligament was simulated with polyether impression material. Fatigue testing was conducted under 5 Hz cyclic loading at 30 degrees to the incisal edge, beginning at 50 N (5,000 cycles) as a warmup. After, the load was increased 100 N every 15,000 cycles until fracture occurred. All specimens were subjected to transillumination, micro-CT analysis, and digital radiography before and after fatigue testing. Fracture mode was classified according to severity and repair potential. Data were analyzed with Kaplan-Meier survival test and post hoc log-rank test (α=0.05) for pairwise comparisons. Results Using FGP significantly increased the number of cycles to failure, irrespective of FGP diameters (p=0.001). The FGP diameters had no statistically significant effect on cycles to failure or failure mode. Conclusion Using FGP without ferrule improved survival rate of structurally severely compromised central incisors compared with rehabilitation without FGP. The diameter of the FGPs had no effect on the survival rate and failure mode.

Metabolomics of silver nanoparticles toxicity in HaCaT cells: structure-activity relationships and role of ionic silver and oxidative stress.

The widespread use of silver nanoparticles (AgNPs) is accompanied by a growing concern regarding their potential risks to human health, thus calling for an increased understanding of their biological effects. The aim of this work was to systematically study the extent to which changes in cellular metabolism were dependent on the properties of AgNPs, using NMR metabolomics. Human skin keratinocytes (HaCaT cells) were exposed to citrate-coated AgNPs of 10, 30 or 60 nm diameter and to 30 nm AgNPs coated either with citrate (CIT), polyethylene glycol (PEG) or bovine serum albumin (BSA), to assess the influence of NP size and surface chemistry. Overall, CIT-coated 60 nm and PEG-coated 30 nm AgNPs had the least impact on cell viability and metabolism. The role of ionic silver and reactive oxygen species (ROS)-mediated effects was also studied, in comparison to CIT-coated 30 nm particles. At concentrations causing an equivalent decrease in cell viability, Ag(+ )ions produced a change in the metabolic profile that was remarkably similar to that seen for AgNPs, the main difference being the lesser impact on the Krebs cycle and energy metabolism. Finally, this study newly reported that while down-regulated glycolysis and disruption of energy production were common to AgNPs and H2O2, the impact on some metabolic pathways (GSH synthesis, glutaminolysis and the Krebs cycle) was independent of ROS-mediated mechanisms. In conclusion, this study shows the ability of NMR metabolomics to define subtle biochemical changes induced by AgNPs and demonstrates the potential of this approach for rapid, untargeted screening of pre-clinical toxicity of nanomaterials in general.

In vitro and in vivo topical delivery studies of tretinoin-loaded ultradeformable vesicles.

INTRODUCTION: Ultradeformable vesicles are highly promising tools to enhance the percutaneous transport of different drugs such as tretinoin across the skin barrier and also to increase the formulation stability at absorption site and reduce the drug induced irritation. METHODS: Topical delivery of tretinoin-loaded ultradeformable vesicles (tretinoin-UDV) was evaluated concerning different studies, such as: the release and permeation profiles (tape stripping); skin penetration (fluorescence analysis); induced electrical changes in skin barrier properties; cytotoxicity (Trypan Blue assay) and skin irritation in in vivo conditions (Draize test). The novel formulation performance was also compared to a commercial tretinoin formulation regarding in vivo studies. RESULTS: It was obtained a sustained and controlled drug release, as expected for UDV formulation. In addition, a dermal delivery was observed regarding the permeation study since it was not detected any drug amount in the receptor phase after 24h. Nile Red-UDV stained intensively mostly in the stratum corneum, corroborating the tape stripping results. Tretinoin-UDV decreased skin resistance, suggesting its ability to induce skin barrier disruption. Finally, the formulation vehicle (empty UDV) and tretinoin-UDV were not toxic under in vitro and in vivo conditions, at least, at 5×10(-3)mg/mL and 0.5mg/mL of tretinoin, respectively. CONCLUSION: Tretinoin-UDV is a promising delivery system for tretinoin dermal delivery without promoting skin irritation (unlike other commercial formulations), which is quite advantageous for therapeutic purpose.

Hepatites B e C nas áreas de três Centros Regionais de Saúde do Estado do Pará, Brasil: uma análise espacial, epidemiológica e socioeconômica / Hepatitis B and C in the areas of three Regional Health Centers of Pará State, Brazil: a spatial, epidemiological and socioeconomic analysis

Resumo Introdução As hepatites virais são graves problemas de saúde pública e estão relacionadas às diferentes características socioeconômicas do território brasileiro. Objetivo Analisar a distribuição espacial das hepatites B e C e sua relação com o Índice de Desenvolvimento Humano Municipal (IDHM) nas áreas de três Centros Regionais de Saúde (CRS), no Estado do Pará, Brasil, de 2010 a 2014. Método Neste trabalho descritivo e transversal, foram utilizados dados do Sistema de Informação de Agravos de Notificação, do Ministério da Saúde, e do Censo 2010, do Instituto Brasileiro de Geografia e Estatística. Resultados As análises mostraram que o 11º CRS notificou o maior número de casos (60,9%). Os indivíduos mais acometidos por ambas as doenças foram do gênero feminino, pardos, adultos e com ensino fundamental. Os fatores de riscos mais significativos foram uso de medicamentos injetáveis e tratamentos dentário e cirúrgico. Foi observada dependência espacial entre o IDHM e os parâmetros da taxa de incidência das doenças, com autocorrelações diretas e indiretas. Assim, áreas com IDHM médio e baixo apresentaram altas taxas de incidência, sobretudo em municípios com intenso fluxo migratório, nas últimas décadas. Conclusão As análises foram eficazes para construir cenários epidemiológicos das doenças. Ressaltamos a necessidade de expandir o controle das hepatites nas áreas estudadas.

Abstract Background Viral hepatitis is a serious public health problem and is related to the different socioeconomic characteristics of the Brazilian territory. Objective To analyze the spatial distribution of the hepatitis B and C and their relationship with the Municipal Human Development Index (IDHM), in the areas of three Regional Health Centers (CRS), in the state of Pará, Brazil, from 2010 to 2014. Method In this descriptive and cross-sectional study, data from the Information System for Notifiable Diseases of the Ministry of Health and the 2010 Census of the Brazilian Institute of Geography and Statistics were used. Results The analyses showed that the 11th CRS reported the greater number of cases (60.9%). The most affected individuals by both diseases were female, brown skin color, adults and elementary school degree. The most significant risk factors were injecting drugs use, dental and surgical treatments. It was observed spatial dependence between the IDHM and the diseases incidence rate parameters, with direct and indirect autocorrelations. Thus, areas with medium and low IDHM showed high incidence rates, especially in municipalities with intense migratory flows, in the last decades. Conclusion The analyses were effective for construct epidemiological scenarios of the diseases. The need to expand the control of hepatitis in the studied areas is highlighted.

Is 3D-CT reformation using free software applicable to diagnosis of bone changes in mandibular condyles?

OBJECTIVES: This study evaluated the agreement of computed tomography (CT) imaging using 3D reformations (3DR) with shaded surface display (SSD) and maximum intensity projection (MIP) in the diagnosis of bone changes in mandibular condyles of patients with rheumatoid arthritis (RA), and compared findings with multiplanar reformation (MPR) images, used as the criterion standard. MATERIAL AND METHODS: Axial CT images of 44 temporomandibular joints (TMJs) of 22 patients with RA were used. Images were recorded in DICOM format and assessed using free software (ImageJ). Each sample had its 3DR-SSD and 3DR-MIP results compared in pairs with the MPR results. RESULTS: Slight agreement (k = 0.0374) was found in almost all comparisons. The level of agreement showed that 3DR-SSD and 3DR-MIP yielded a number of false-negative results that was statistically significant when compared with MPR. CONCLUSIONS: 3DR-SSD or 3DR-MIP should only be used as adjuvant techniques to MPR in the diagnosis of bone changes in mandibular condyles.

Dimensional error of selective laser sintering, three-dimensional printing and PolyJet models in the reproduction of mandibular anatomy.

BACKGROUND: Selective laser sintering (SLS), three-dimensional printing (3DP) and PolyJet are rapid prototyping (RP) techniques to fabricate prototypes from virtual biomedical images. To be used in maxillofacial surgery, these models must accurately reproduce the craniofacial skeleton. PURPOSE: To analyze the capacity of SLS, 3DP and PolyJet models to reproduce mandibular anatomy and their dimensional error. MATERIAL: Dry mandible, helical CT images, SLS, 3DP and PolyJet prototypes, and digital electronic caliper. METHODS: Helical CT images were acquired from a dry mandible (criterion standard) and manipulated with the InVesalius software. Prototypes were produced using SLS, 3DP and PolyJet techniques. Thirteen linear measurements of each prototype were made and compared with the dry mandible measurements. RESULTS: The results showed a dimensional error of 1.79%, 3.14% and 2.14% for SLS, 3DP and PolyJet models, respectively. The models satisfactorily reproduced anatomic details and the SLS and PolyJet prototypes showed greater dimensional precision and reproduced mandibular anatomy more accurately than the 3DP model. CONCLUSIONS: The SLS prototype had a greater dimensional accuracy than the PolyJet and 3DP models. The PolyJet technique reproduced anatomic details of the mandible more accurately.

Dentes retidos: novas perspectivas de localização / Impacted teeth: new diagnostic perspectives

As radiografias convencionais são úteis e fáceis de usar para o diagnóstico de dentes retidos, porém, pela característica de fornecerem imagens bidimensionais e sobrepostas, dificultam o planejamento da cirurgia. O uso da tomografia computadorizada tem se difundido por permitir a visualização de pequenas estruturas anatômicas maxilofaciais relevantes para intervenções cirúrgicas e por possibilitar a visualização das suas relações espaciais em três dimensões. Objetivo e relato dos casos: Relatar os casos de dois pacientes que apresentavam dentes retidos na região anterior da maxila, os quais foram avaliados por tomografia computadorizada. Discutem-se especificidades deste moderno método de diagnóstico por imagem e as vantagens clínicas advindas dessas imagens, pois foi possível identificar a localização precisa dos dentes retidos, a distância das corticais, de acidentes anatômicos e de outros dentes. Considerações finais: A tomografia computadorizada mostrou ser um exame complementar muito importante e preciso para o diagnóstico planejamento cirúrgico e controle pós-operatório de dentes retidos.