Optimization of an Analytical Protocol for the Extraction of Microplastics from Seafood Samples with Different Levels of Fat.

Marine organisms are affected by the ubiquitous occurrence of microplastics (MPs) in the environment. Several protocols have been described to extract and quantify MPs in seafood, although their complex matrices, with high level of fat, can compromise the efficiency of MPs extraction. To solve this issue, the present study aimed to develop a detailed methodology suitable to process seafood samples with different levels of fat, namely fish and molluscs, from fresh and canned sources, including the immersive liquids from the cans. Sample digestion was tested using different solutions (10% KOH, 30% H2O2), temperatures (40 °C, 65 °C) and incubation times (24, 48, 72 h). For fat removal, three detergents (two laboratory surfactants and a commercial dish detergent) and 96% ethanol were tested, as well as the manual separation of fat. The methodology optimized in this study combined a digestion with 30% H2O2 at 65 °C, during 24 to 48 h, with a manual separation of the fat remaining after the digestion. All steps from the present methodology were tested in six types of polymers (PE-LD, PET, PE, AC, PS, and lycra), to investigate if these procedures altered the integrity of MPs. Results showed that the optimized methodology will allow for the efficient processing of complex seafood samples with different fat levels, without compromising MPs integrity (recoveries rate higher than 89% for all the polymers tested).

Loops around the Heme Pocket Have a Critical Role in the Function and Stability of BsDyP from Bacillus subtilis.

Bacillus subtilis BsDyP belongs to class I of the dye-decolorizing peroxidase (DyP) family of enzymes and is an interesting biocatalyst due to its high redox potential, broad substrate spectrum and thermostability. This work reports the optimization of BsDyP using directed evolution for improved oxidation of 2,6-dimethoxyphenol, a model lignin-derived phenolic. After three rounds of evolution, one variant was identified displaying 7-fold higher catalytic rates and higher production yields as compared to the wild-type enzyme. The analysis of X-ray structures of the wild type and the evolved variant showed that the heme pocket is delimited by three long conserved loop regions and a small α helix where, incidentally, the mutations were inserted in the course of evolution. One loop in the proximal side of the heme pocket becomes more flexible in the evolved variant and the size of the active site cavity is increased, as well as the width of its mouth, resulting in an enhanced exposure of the heme to solvent. These conformational changes have a positive functional role in facilitating electron transfer from the substrate to the enzyme. However, they concomitantly resulted in decreasing the enzyme's overall stability by 2 kcal mol-1, indicating a trade-off between functionality and stability. Furthermore, the evolved variant exhibited slightly reduced thermal stability compared to the wild type. The obtained data indicate that understanding the role of loops close to the heme pocket in the catalysis and stability of DyPs is critical for the development of new and more powerful biocatalysts: loops can be modulated for tuning important DyP properties such as activity, specificity and stability.

Peptidases from latex of Carica candamarcensis upregulate COX-2 and IL-1 mRNA transcripts against Salmonella enterica ser. Typhimurium-mediated inflammation.

The immunomodulatory properties of a mixture of cysteine peptidases (P1G10) obtained from the fruit lattice of Carica candamarcensis were investigated. P1G10 was obtained from fresh latex samples by chromatography in a Sephadex column and initially administered to Swiss mice (n = 5; 1 or 10 mg/kg) via i.p. After 30 min, the mice were injected with carrageenan (0.5 mg/mouse) or heat-killed S. Typhimurium (10(7) CFU/mL; 100°C/30 min) into the peritoneal cavity. Afterwards, two animal groups were i.p. administered with P1G10 (n = 6; 1, 5, or 10 mg/Kg) or PBS 24 hours prior to challenge with live S. Typhimurium (10(7) CFU/mL). P1G10 stimulated the proliferation of circulating neutrophils and lymphocytes, 6 h after injection of carrageenan or heat-killed bacteria, respectively. Furthermore, survival after infection was dose-dependent and reached 60% of the animal group. On the other hand, control mice died 1-3 days after infection. The examination of mRNA transcripts in liver cells 24 h after infection confirmed fold variation increases of 5.8 and 4.8 times on average for IL-1 and COX-2, respectively, in P1G10 pretreated mice but not for TNF-α, IL-10, γ-IFN and iNOS, for which the results were comparable to untreated animals. These data are discussed in light of previous reports.

Uncovering microplastics contamination in canned seafood.

There is limited research on the occurrence of microplastics (MPs) in canned seafood. All types of canned seafood investigated in the present study were contaminated. After sample digestion in 30 % hydrogen peroxide, a total of 40 MPs were recovered. Fibers were the most common type, blue was the dominant colour, and Fourier Transform Infrared Spectroscopy (FTIR) identified polyester as the most common polymer. Considering all samples, an average of 3.5 ± 5.2 MPs/can was obtained, with octopus in tomato sauce and tuna in olive oil presenting the highest contamination (5.2 ± 7.5 MPs/can and 5.2 ± 5.1 MPs/can, respectively). Also, significant differences between the number of MPs in the seafood tissues and immersion liquids were verified. The present study demonstrates MPs occurrence in canned seafood, a potential contamination pathway for humans. More research on the different stages of the canning processing is vital for understanding MPs contamination in cans.

A wide array of lignin-related phenolics are oxidized by an evolved bacterial dye-decolourising peroxidase.

Lignin is the second most abundant natural polymer next to cellulose and by far the largest renewable source of aromatic compounds on the planet. Dye-decolourising peroxidases (DyPs) are biocatalysts with immense potential in lignocellulose biorefineries to valorize emerging lignin building blocks for environmentally friendly chemicals and materials. This work investigates the catalytic potential of the engineered PpDyP variant 6E10 for the oxidation of 24 syringyl, guaiacyl and hydroxybenzene lignin-phenolic derivatives. Variant 6E10 exhibited up to 100-fold higher oxidation rates at pH 8 for all the tested phenolic substrates compared to the wild-type enzyme and other acidic DyPs described in the literature. The main products of reactions were dimeric isomers with molecular weights of (2 × MWsubstrate - 2 H). Their structure depends on the substitution pattern of the aromatic ring of substrates, i.e., of the coupling possibilities of the primarily formed radicals upon enzymatic oxidation. Among the dimers identified were syringaresinol, divanillin and diapocynin, important sources of structural scaffolds exploitable in medicinal chemistry, food additives and polymers.

Microplastic contamination in large migratory fishes collected in the open Atlantic Ocean.

Fishes are one of the most important components of the oceans and are exposed to several anthropogenic pressures, namely microplastic (MP), contaminants that are now ubiquitous worldwide. Taking advantage of the 2020 Circumnavigation Expedition carried by the NRP Sagres tall ship of the Portuguese Navy, fish samples from the southern Atlantic ocean were collected to evaluate possible MP contamination. In a total of 14 weeks of campaign, seven large migratory fishes of commercial interest were collected across the middle Atlantic Ocean and along the South American Atlantic coast. All individuals were contaminated with MPs, with an average of 18 ± 11 MPs/fish. In all fish sampled, both the gastrointestinal tract and gills presented MPs, indicating different contamination pathways including via their preys and from surrounding water, respectively. A total of 124 MPs were observed, where 72 % were fibers and 28 % particles, mostly of blue color (85 %), and with rayon and nylon as the most abundant polymers. This study is an important contribution to increase the scientific knowledge of MP contamination in mesopelagic fishes used for human consumption and collected in the open waters, reinforcing the need for further research regarding MP contamination in top predatory species from high trophic levels.

Biocatalysis for biorefineries: The case of dye-decolorizing peroxidases.

Dye-decolorizing Peroxidases (DyPs) are heme-containing enzymes in fungi and bacteria that catalyze the reduction of hydrogen peroxide to water with concomitant oxidation of various substrates, including anthraquinone dyes, lignin-related phenolic and non-phenolic compounds, and metal ions. Investigation of DyPs has shed new light on peroxidases, one of the most extensively studied families of oxidoreductases; still, details of their microbial physiological role and catalytic mechanisms remain to be fully disclosed. They display a distinctive ferredoxin-like fold encompassing anti-parallel ß-sheets and α-helices, and long conserved loops surround the heme pocket with a role in catalysis and stability. A tunnel routes H2O2 to the heme pocket, whereas binding sites for the reducing substrates are in cavities near the heme or close to distal aromatic residues at the surface. Variations in reactions, the role of catalytic residues, and mechanisms were observed among different classes of DyP. They were hypothetically related to the presence or absence of distal H2O molecules in the heme pocket. The engineering of DyPs for improved properties directed their biotechnological applications, primarily centered on treating textile effluents and degradation of other hazardous pollutants, to fields such as biosensors and valorization of lignin, the most abundant renewable aromatic polymer. In this review, we track recent research contributions that furthered our understanding of the activity, stability, and structural properties of DyPs and their biotechnological applications. Overall, the study of DyP-type peroxidases has significant implications for environmental sustainability and the development of new bio-based products and materials with improved end-of-life options via biodegradation and chemical recyclability, fostering the transition to a sustainable bio-based industry in the circular economy realm.

Positive Synergistic Effect of Adhesives and Resin Cements Containing an Iodonium Salt on Bonding of Fiber Posts.

PURPOSE: To evaluate the push-out bond strength (PBS) of glass-fiber posts (GFP) in different root canal zones (cervical, middle, and apical), bonded with experimental simplified adhesives (ESAs) containing different initiator systems (camphorquinone [CQ] or phenylpropanodione [PPD]) with or without diphenyl iodonium hexafluorophosphate (DPI), in combination with a DPI-containing composite cement. MATERIALS AND METHODS: ESA blends were prepared with bisphenol glycidyl methacrylate (bis-GMA), triethylene glycol dimethacrylate (TEG-DMA), 1,3-glycerol dimethacrylate (GDMA), 2-hydroxyethyl methacrylate (HEMA), and ethanol, then divided into 12 experimental groups (n = 10) according to the initiator systems (CQ, PPD, or CQ + PPD) and the presence or absence of DPI. The roots of 120 extracted bovine incisors were prepared with #5 Largo drills and the GFP were cemented with each ESA and experimental composite cements containing 0.05 mol% of DPI. The push-out bond strength (PBS) test was performed after 24 h of storage. Failure patterns were analyzed under a stereomicroscope. Data were analyzed with split-plot two-way ANOVA and Tukey's test (α = 0.05). RESULTS: PBS was significantly higher for DPI-containing ESAs in all regions evaluated, with the group containing 0.5 CQ + 1 PPD + 0.5 DPI exhibiting the highest PBS. There was no statistically signficant difference among groups without DPI. Most failures were classified as adhesive at the cement-dentin interface. CONCLUSIONS: The combination of an adhesive and a composite cement containing DPI salt can improve GFP bonding to root dentin, even in the apical region.

The impact of sediment dumping sites on the concentrations of microplastic in the inner continental shelf of Rio de Janeiro/Brazil.

The marine environment is constantly being impacted by anthropogenic activities. Nowadays, microplastics (MPs) representing one of the most deleterious material among of all substances and material from anthropogenic origin. The Microplastics (MPs) are particles smaller than 5 mm. This study presents information on abundance, distribution, type and colour of microplastics in the bottom sediments of the continental Shelf of Rio de Janeiro State. This area is strongly impacted due to its location in front of one of the most polluted coastal bays in the Brazilian Coastline. It receives untreated sewage from an Ipanema Beach submarine emissary and also a great amount of sediments dredged from Rio de Janeiro Harbour, which strongly influences the distribution of MPs in the area. The analyses detected the presence of MP in 100% of the samples, composed mainly by secondary microplastics, and almost 50% were fibers, followed by plastic films, plastic fragments and pellets. Based on the nature of the sources of the MP, a great variety of colours was shown, dominated by four main colours: blue, white, transparent, and black, this pattern could potentially increase their bioavailability due to resemblance to prey items, especially to visual raptorial species.

Influence of ethanol on dentin roughness, surface free energy, and interaction between AH Plus and root dentin.

This study aimed to evaluate the influence of different ethanol concentrations on dentin roughness, surface free energy, and contact angle between AH Plus and the root canal dentin. One hundred human maxillary anterior teeth were split longitudinally and 200 dentin specimens were polished to make the surface flatter and smoother. An acrylic bar was positioned between two dentin specimens and impression material was added to create a block, simulating an instrumented root canal space. Specimens were removed from the mold and cleaned in an ultrasonic bath for 10 min. Thereafter, dentin specimens were divided into four groups (n = 50) according to the drying methods used: a) wet: vacuum only, b) paper points: vacuum + absorbent paper points, c) 70% alcohol: 70% alcohol (1 min) + vacuum + absorbent paper points, and d) 100% alcohol: 100% alcohol (1 min) + vacuum + absorbent paper points. A rugosimeter and a goniometer were used to verify the roughness (Ra) and to measure the surface free energy and the contact angle between the AH Plus sealer and the root canal dentin. ANOVA and Tukey tests (α = 0.05) were used for statistical analysis. The 70% and 100% ethanol groups showed significantly decreased roughness as well as increased surface free energy in the root canal dentin when compared to the wet and paper point groups. In addition, ethanol significantly reduced the contact angle between the AH Plus sealer and the root canal dentin. Ethanol solutions (70% and 100%) provide better wettability of AH Plus sealer on dentin surfaces.

Accuracy of mandibular measurements of sexual dimorphism using stabilizer equipment.

The objective of this investigation was to compare the accuracy of mandibular measurements using a stabilizer (MS) with gold standard computed tomography (GS) images. Sixty mandibles were studied. Werth TomoScope HV Compact® was used to obtain CT images (GS), and the MS was also used. Analysis of the CT scans was performed using the VG Studio Max software® (Volume Graphics GmbH, Heidelberg, Germany), and MS was used after the proper positioning of the mandible. Descriptive and paired t test measures were used, and a ROC curve was calculated, as well as sensibility and specificity. MedCalc and STATA 13.0® were used (95% level of significance). Bicondylar breadth, bicoronoid breadth and minimum ramus breadth reached the highest concordance correlation coefficients at 0.99 (0.99-1.00), 0.99 (0.99-1.00) and 1.00 (0.99-1.00), respectively. Comparing observers with GS, the lowest accuracy was noted for the maximum mandibular length [0.59 (0.45-0.69), 0.64 (0.51-0.74)], the breadth of the right (0.14 (0.04-0.23), 0.14 (0.004-0.24)) and left mandibular body [0.14 (0.03-0.24), 0.16 (0.05-0.26)], and the right [0.58 (0.45-0.69), 0.63 (0.51-0.73) and left (0.59 (0.45-0.70), 0.59 (0.46-0.69)] mandibular angle. Various measurements exhibited good sensibility for males using MS: maximum mandibular length (78.12), bicondylar breadth (78.12), left mandibular notch breadth (84.37), and the left height of the mandibular body at the mental foramen (75.00). High specificity in discriminating females was observed for the left maximal ramus height (85.19), mandibular length (85.71), bicoronoid breadth (96.43), right height of the mandibular body at the mental foramen (82.19), bimental breadth (78.57), breadth right (92.86) and left (96.43) mandibular body, minimum ramus breadth (89.29), and left mandibular angle (85.71). MS was able to discriminate sexual dimorphism.

Tratamento de ceratocistos na síndrome de Gorlin Goltz / Diagnosis and treatment of oral keratocysts in Gorlin Goltz Syndrome / Tratamento de ceratocistos na Síndrome de Gorlin Goltz

A Síndrome de Gorlin Goltz apresenta características com comprometimento craniofaciais que incluem carcinomas basocelulares, ceratocístos odontogênicos e fenda labial e/ou palatina. Ceratocísticos odontogênico aparecem durante as primeiras décadas de vida, mais comumente na mandíbula, associados a dentes impactados. O diagnóstico precoce possibilita a cura da lesão, minimiza as deformidades ósseas e pode ser concluído com exames como radiográfico e histopatológico. Relato de caso: Com o objetivo descrever o diagnóstico e analisar as possibilidades de tratamento das manifestações faciais da Síndrome de Gorlin Goltz será relatado um caso clínico de uma paciente infantil. A paciente tem um acompanhamento clínico multidisciplinar com geneticista, oncologista e cirurgião-dentista de 6 anos. Apresentou 5 ceratocisticos odontogênicos, carcinomas basocelulares na região do pescoço, calcificação da foice cerebral, ceratose palmo-plantar e macrocefalia. O tratamento para as lesões císticas foi a enucleação, seguida de osteotomia periférica. O defeito ósseo produzido pela enucleação de cisto mandibular foi enxertado com bloco de osso alógeno do banco de tecidos do INTO-RJ. Conclusão: Constata-se que o Cirurgião-dentista é capacitado para fazer o diagnóstico desta síndrome e encaminhar para o tratamento multidisciplinar. O enxerto alógeno é uma opção adequada de reconstrução de cavidades císticas, beneficiando pacientes do Sistema Único de Saúde... (AU)

Gorlin Goltz Syndrome has features with craniofacial involvement that include basal cell carcinomas, odontogenic keratocysts, and cleft lip and/or palate. Odontogenic keratocysts appear during the first decades of life, most commonly in the mandible, associated with impacted teeth. Early diagnosis enables healing of the lesion, minimizes bone deformities and can be completed with exams such as radiographic and histopathological exams. Case report: In order to describe the diagnosis and analyze the treatment possibilities of the facial manifestations of Gorlin Goltz Syndrome, a clinical case of a child patient will be reported.The patient has a multidisciplinary clinical follow-up with a 6-year geneticist, oncologist and dental surgeon. She had 5 odontogenic keratocystic keratocysts, basal cell carcinomas in the neck region, sickle cerebral calcification, palmoplantar keratosis and macrocephaly. The treatment for cystic lesions was enucleation, followed by peripheral osteotomy. The bone defect produced by the enucleation of a mandibular cyst was grafted with an allogeneic bone block from the tissue bank of INTO-RJ. Conclusion: It is concluded that the dentist is trained to make the diagnosis of this syndrome and refer to multidisciplinary treatment. Allogeneic graft is an appropriate option for the reconstruction of cystic cavities, benefiting patients from the Unified Health System... (AU)

El Síndrome de Gorlin Goltz tiene características con compromiso craneofacial que incluyen carcinomas de células basales, queratoquistes odontogénicos y labio leporino o paladar hendido. Los queratoquistes odontogénicos aparecen durante las primeras décadas de vida, más comúnmente en la mandíbula, asociados con dientes retenidos. El diagnóstico precoz permite la curación de la lesión, minimiza las deformidades óseas y se puede concluir con exámenes como exámenes radiográficos e histopatológicos. Reporte de caso: Con el fin de describir el diagnóstico y analizar las posibilidades de tratamiento de las manifestaciones faciales del Síndrome de Gorlin Goltz, se reportará un caso clínico de un paciente infantil. El paciente tiene un seguimiento clínico multidisciplinario con un genetista, oncólogo y cirujano dentista de 6 años. Presentó 5 queratocísticos odontogénicos, carcinomas basocelulares en la región del cuello, calcificación de la hoz cerebral, queratosis palmoplantar y macrocefalia. El tratamiento de las lesiones quísticas fue la enucleación, seguida de una osteotomía periférica. El defecto óseo producido por la enucleación de un quiste mandibular se injertó con un bloque óseo alogénico del banco de tejidos de INTO-RJ. Conclusión: Parece que el odontólogo está capacitado para realizar el diagnóstico de este síndrome y derivar al tratamiento multidisciplinario. El injerto alogénico es una opción adecuada para la reconstrucción de cavidades quísticas, beneficiando a los pacientes del Sistema Único de Salud... (AU)

Latex protein extracts from Calotropis procera with immunomodulatory properties protect against experimental infections with Listeria monocytogenes.

BACKGROUND: The latex from the medicinal plant Calotropis procera is often used in folk medicine against infectious and inflammatory diseases. PURPOSE: In this study, we investigate a protein fraction with immunomodulatory properties, named LPPI, against experimental infections, in vitro and in vivo, with a virulent strain of Listeria monocytogenes. STUDY DESIGN: LPPI was exposed to cultured macrophages or Swiss mice and then challenged with L. monocytogenes. METHODS: Peritoneal macrophages were obtained from Swiss mice, and cultured in 96-well microplates. Soluble latex proteins (LP) were subjected to fractionation by ion-exchange chromatography. The major peak (LPPI) was added into wells at 10 or 100µg/ml. Albumin (100µg/ml) was used for comparison between protein treatments. After incubation for 1h at 5% CO2/ 37°C, the supernatant was discarded and 0.2ml of L. monocytogenes overnight culture was added in the wells. Following 4h and 24h infection, the cytokine mRNA expression was evaluated as well as the number of intracellular colony forming units. Swiss mice (n=16) were injected intraperitoneally (i.p.) with LPPI (5 and 10mg/kg) while the control mice received albumin (10mg/kg) or LP (10mg/kg). After 24h, all animal groups were challenged with L. monocytogenes (10(6) CFU/ ml), also by i.p. route. RESULTS: LPPI was not toxic to uninfected macrophages (pMØ) and significantly increased mRNA expression of TNF-α, IL-6, IL-1ß and iNOS. Following infection, cell viability was reduced by 50% in albumin-treated pMØ (control); but only 17% in pMØ treated with LPPI at 100µg/ml. In this case, LPPI increased expression of TNF-α and IL-6 whereas the number of bacterial colony-forming units was reduced 100-fold in comparison to control groups. Swiss mice pretreated with LPPI showed dose-dependent survival rates that reached 80%, while mice that received albumin died 1-3 days after infection. After 24h infection, leukocyte migration to the infectious foci was high in LPPI-treated mice whereas the number of viable bacteria in the peritoneal fluid, liver and bloodstream were significantly reduced. CONCLUSION: We conclude that LPPI present immunomodulatory properties that are beneficial for prevention of systemic bacterial infections caused by the intracellular bacteria L. monocytogenes.

Effect of ethanol-conditioned dentine on sealer penetration into dentinal tubules: a confocal microscopy study

Aim: The aim of this study was to evaluate the effect of ethanol-conditioned dentin on endodontic sealer penetration into dentinal tubules by confocal laser scanning microscopy (CLSM). Methods: Forty human maxillary anterior teeth were instrumented and divided into four groups (n = 10) according to the drying methods: 1) wet: vacuum only, 2) paper points: vacuum + absorbent paper points, (3) 70% ethanol: 70% ethanol (1 min) + vacuum + absorbent paper points, and (4) 100% ethanol: 100% ethanol (1 min) + vacuum + absorbent paper points. All root canals were filled with resin-based endodontic sealer. Four sections from each third (cervical, middle, and apical) were examined by CLSM. Root canal wall perimeter infiltrated by sealer, maximum depth of sealer penetration, percentage of penetrated area, and fluorescence intensity of rhodamine B were measured. Statistical analysis was performed by analysis of variance and Tukey's tests (α = 0.05). Results: No statistical difference was found when percentage of root canal wall coverage infiltrated by sealer were compared. The groups in which ethanol solutions were used presented greater depth of sealer penetration, higher percentage of penetrated area, and higher fluorescence intensity of rhodamine B (p< 0.05) when compared with the wet and paper point groups. Overall, 100% ethanol produced better results than 70% ethanol, except for rhodamine B intensity (cervical third). In addition, the absorbent paper points drying method behaved better than did vacuum only group, except for rhodamine B intensity (apical third). Conclusion: Ethanol-conditioned dentin improved the penetration of resin-based sealer into dentinal tubules, especially at the concentration of 100%

Self-adjusting file cleaning-shaping-irrigation system improves root-filling bond strength.

INTRODUCTION: The aim of the present study was to assess the bond strength of root fillings in oval-shaped canals prepared with the self-adjusting file (SAF) system. METHODS: A careful specimen selection resulted in 2 equal groups, each consisting of 12 extracted mandibular canines with oval canals that had vital pulps before extraction. One group was subjected to the SAF protocol, and the other group underwent conventional protocol, which was the ProTaper system with syringe-needle irrigation. Full-strength sodium hypochlorite was used as an irrigant for both groups. The teeth were obturated in a standardized way, filled with a lentulo spiral as the root filling, and then prepared for micropush-out assessment by using root slices of 1-mm thickness. Loading was performed on a universal testing machine at a speed of 0.5 mm/min(-1). The Student's t test for pairwise comparisons was applied to assess the effect of each preparation technique on the push-out bond strength. RESULTS: All specimens showed measurable adhesive properties to root dentin. In addition, no premature failure occurred. The group-by-location interaction was significant (P = .0071); thus, the group comparisons were dependent on the canal third. Overall, the push-out bond strength was the highest in the coronal third and the lowest in the apical third. SAF-prepared specimens displayed significantly higher bond strengths (P = .0012, 0.51-5.9 MPa). CONCLUSIONS: The present study showed that SAF preparation markedly influenced root-filling push-out bond strength in oval-shaped canals. Further investigations are needed to provide a better understanding of the physicochemical modifications of the root dentin prepared with the SAF cleaning-shaping-irrigation system.

Influence of ethanol on dentin roughness, surface free energy, and interaction between AH Plus and root dentin

Abstract This study aimed to evaluate the influence of different ethanol concentrations on dentin roughness, surface free energy, and contact angle between AH Plus and the root canal dentin. One hundred human maxillary anterior teeth were split longitudinally and 200 dentin specimens were polished to make the surface flatter and smoother. An acrylic bar was positioned between two dentin specimens and impression material was added to create a block, simulating an instrumented root canal space. Specimens were removed from the mold and cleaned in an ultrasonic bath for 10 min. Thereafter, dentin specimens were divided into four groups (n = 50) according to the drying methods used: a) wet: vacuum only, b) paper points: vacuum + absorbent paper points, c) 70% alcohol: 70% alcohol (1 min) + vacuum + absorbent paper points, and d) 100% alcohol: 100% alcohol (1 min) + vacuum + absorbent paper points. A rugosimeter and a goniometer were used to verify the roughness (Ra) and to measure the surface free energy and the contact angle between the AH Plus sealer and the root canal dentin. ANOVA and Tukey tests (α = 0.05) were used for statistical analysis. The 70% and 100% ethanol groups showed significantly decreased roughness as well as increased surface free energy in the root canal dentin when compared to the wet and paper point groups. In addition, ethanol significantly reduced the contact angle between the AH Plus sealer and the root canal dentin. Ethanol solutions (70% and 100%) provide better wettability of AH Plus sealer on dentin surfaces.

Accuracy of mandibular measurements of sexual dimorphism using stabilizer equipment

Abstract The objective of this investigation was to compare the accuracy of mandibular measurements using a stabilizer (MS) with gold standard computed tomography (GS) images. Sixty mandibles were studied. Werth TomoScope HV Compact® was used to obtain CT images (GS), and the MS was also used. Analysis of the CT scans was performed using the VG Studio Max software® (Volume Graphics GmbH, Heidelberg, Germany), and MS was used after the proper positioning of the mandible. Descriptive and paired t test measures were used, and a ROC curve was calculated, as well as sensibility and specificity. MedCalc and STATA 13.0® were used (95% level of significance). Bicondylar breadth, bicoronoid breadth and minimum ramus breadth reached the highest concordance correlation coefficients at 0.99 (0.99-1.00), 0.99 (0.99–1.00) and 1.00 (0.99–1.00), respectively. Comparing observers with GS, the lowest accuracy was noted for the maximum mandibular length [0.59 (0.45–0.69), 0.64 (0.51–0.74)], the breadth of the right (0.14 (0.04–0.23), 0.14 (0.004–0.24)) and left mandibular body [0.14 (0.03–0.24), 0.16 (0.05-0.26)], and the right [0.58 (0.45–0.69), 0.63 (0.51–0.73) and left (0.59 (0.45–0.70), 0.59 (0.46–0.69)] mandibular angle. Various measurements exhibited good sensibility for males using MS: maximum mandibular length (78.12), bicondylar breadth (78.12), left mandibular notch breadth (84.37), and the left height of the mandibular body at the mental foramen (75.00). High specificity in discriminating females was observed for the left maximal ramus height (85.19), mandibular length (85.71), bicoronoid breadth (96.43), right height of the mandibular body at the mental foramen (82.19), bimental breadth (78.57), breadth right (92.86) and left (96.43) mandibular body, minimum ramus breadth (89.29), and left mandibular angle (85.71). MS was able to discriminate sexual dimorphism.

Evaluation of foraminal transportation during foraminal enlargement with different instrumentation systems

Aim: To evaluate the foraminal transportation during foraminal enlargement after manual instrumentation with stainless steel files, preparation with the Mtwo system and Reciproc R25 file. Methods: Thirty roots were selected, divided in three groups and prepared in accordance with the different instrumentation systems: Hand Files (HF); Mtwo system (MS); and Reciproc system (RS). All groups were prepared with the instrumentation level 1 mm beyond the apex. Photomicrographs were performed using scanning electron microscopy, to record the foraminal anatomy before and after instrumentation. Data were analyzed using ANOVA followed by Tukey's test with a significance level of 5%. Results: The group instrumented with hand files showed higher foraminal transportation when compared to the Mtwo and Reciproc groups (p<0.05). Reciproc group showed lower transportation when compared to the Mtwo group (p<0.05). Conclusions: The stainless steel files caused significant foraminal transportation, while Reciproc system showed safe apical preparation, with little transportation.

Periodontal findings and other oral manifestations in Proteus syndrome: a case report.

Proteus syndrome is an extremely rare congenital disorder with progressive asymmetric overgrowth of multiple tissues. The etiology is unknown to date. The aim of this article was to describe the clinical and radiographic periodontal findings and other oral manifestations in a patient with Proteus syndrome. A 13-year-old Caucasian Brazilian girl with Proteus syndrome was evaluated by means of clinical examination and full-mouth intraoral radiographic analysis. The patient showed skeletal malformations; gigantism; facial phenotype; and overgrowth of multiple tissues, including disproportionate overgrowth of skull, left hand, and lower limbs. Evaluation of the plantar surface of the left foot showed cerebriform connective nevus. The hands also showed reduced range of motion. Intraoral examination revealed enamel hypoplasia of permanent teeth restricted to the left side of the mouth, generalized gingival overgrowth, abundant dental plaque, and malpositioned teeth. Neither periodontal pockets nor alveolar bone destruction were detected. In conclusion, oral manifestations of Proteus syndrome may include gingival overgrowth and malposition of teeth, as well as unilateral enamel hypoplasia, as shown in this case report.

Comparação de Dois Métodos de Antissepsia Pré-operatória de Mãos em Cirurgia Bucal / Comparison Between Two Methods of Preoperative Antisepsis of Hands in Oral Surgery

Objetivo: Este trabalho teve como objetivo avaliar a eficácia da escovação pré-operatória, efeito imediato e residual de dois antissépticos na redução bacteriana das mãos, previamente a procedimentos cirúrgicos bucais ambulatoriais. Metodologia: Para a realização do experimento, foram selecionados 20 acadêmicos de odontologia, que participaram de quatro grupos experimentais: grupo I, utilizando o polivinilpirrolidona-iodo (PVP-I) a 10% degermante associado à técnica de escovação cirúrgica, promovendo antissepsia mecânica e química; grupo II, PVP-I a 10% e o método de lavagem cirúrgica, realizando somente antissepsia química; grupo III, clorexidina a 2% associado à técnica de escovação cirúrgica; grupo IV, clorexidina a 2% realizando a técnica de lavagem cirúrgica. Resultado: Como resultado do efeito residual, o grupo I apresentou, em média, de 71% de redução bacteriana; o grupo II apresentou 83%; o grupo III, 97% de ação antimicrobiana, e o grupo IV demonstrou aproximadamente 97% de efeito bactericida. Conclusão: Ao se observar em dois grupos que utilizaram a mesma solução antisséptica em relação ao método de lavagem cirúrgica das mãos, ou seja, sem o uso de artefatos, este apresentou resultados melhores ou, no mínimo, semelhantes quanto à redução bacteriana em relação à técnica convencional de escovação cirúrgica. Com relação à solução antisséptica, a clorexidina apresentou maior redução da carga microbiana que o PVP-I.

Purpose: The purpose of this study was to evaluate the effectiveness of preoperative brushing, the immediately and residual effect of the antiseptics on bacterial reduction of hands, before the oral surgical procedures. Methodology: To the experiment, were selected 20 students of dentistry, who participated in four experimental groups: group I, using povidone-iodine (PVP-I) 10% degerming associated with hand-scrubbing, mechanical and chemical antisepsis; group II, PVP-I 10% and hand-rubbing, performing only chemical antisepsis; group III, digluconate of the chlorhexidine 2% solution degermante with hand-scrubbing; group IV, chlorhexidine 2% and hand-rubbing. Results: As a result of residual effect, the group I made on average 71% of bacterial reduction, while the group II showed 83%; group III resulted in 97% of antimicrobial action, the group IV showed approximately 97% of bactericidal effect. Conclusion: Noting that both groups used the same anti-septic solution to hand-rubbing method showed better at least similar results in bacterial reduction than hand-scrubbing. About the anti-septic solution the chlorhexidine showed greater reduction of microbial load that the PVP-I.