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PURPOSE: This two-arm parallel randomized controlled trial aimed to evaluate and compare periodontal changes due to rapid maxillary expansion (RME) using tooth-bone-borne and tooth-borne devices in growing patients via clinical examinations and cone-beam computed tomography (CBCT). MATERIALS AND METHODS: Forty-two eligible patients (aged 11-14 years; transverse maxillary deficiency, posterior crossbite) were screened and divided into two groups based on the treatment received (randomization was performed using computer-generated numeric sequences): hybrid hyrax tooth-bone-borne group (TBB) and hyrax tooth-borne group (TB). The primary outcome was the change in cortical bone thickness (by CBCT). In addition, the clinical attachment level (CAL), gingival recession, and bleeding were assessed. Both examinations were performed before and 3 months after the activation phase. Intergroup comparisons were performed using analysis of covariance (ANCOVA; P < 0.05). RESULTS: Twenty-one patients (12 girls and 9 boys; mean initial age, 13.3 years) were included in the TBB group and 21 (5 girls and 16 boys; mean initial age, 13.2 years) were included in the TB group. The TB group exhibited a decrease in buccal bone thickness in the first premolars and first molars at all three evaluated levels. Specifically, tooth 14 at 3 mm from the enamel-cement junction showed a significant width reduction (0.7 mm; p < 0.001), accompanied by a notable increase in palatal cortical thickness at 6 mm of enamel-cement junction (1.13 mm; p < 0.001). CONCLUSIONS: RME resulted in buccal bone thickness reduction at the first premolar with hyrax treatment. In the molar region, both devices resulted in cortical bone alterations that were less pronounced in the TBB group.

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Implant-supported complete dentures are a common procedure for patients with mandibular edentulism problems. This article documents the protocol for immediate functional loading of fixed transient mandibular prostheses with fully moldable attachments and distal extensions to prevent fractures. A 56-year-old female patient was referred to the Oral Rehabilitation and Implantology Service due to periodontal problems, difficulty in chewing capacity and aesthetic compromise. The patient was treated in a single surgical procedure with dental extractions, guided regularization of the alveolar process and guided placement of five interforaminal implants and placement of functional fixed mandibular prostheses with immediate loading with personalized UCLA'S, distal extensions and short arc occlusal scheme. At 3 months postoperatively, the definitive placement of fixed mandibular metal acrylic prostheses and conventional upper prostheses was performed. The functional and aesthetic integrity of the fixed mandibular prosthesis implant preserved with UCLA'S documents that implant placement in the interforaminal zone with an immediate loading protocol is a viable treatment option for prosthetic rehabilitation of the fully edentulous mandibular arch and that design with distal extensions in the posterior sector of the mandibular arch is an effective option to avoid fracture of the prostheses, presenting a survival of the five mandibular implants of 100% at 1 year postoperatively.

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Gasification is a thermochemical process that has gained significant interest in the field of biomass energy conversion. Despite the level of technological maturity of the process, the dynamic variation of the process as a result of changes in both the properties of the gasifying agent and biomass has not been analysed in sufficient depth. Therefore, the present study characterizes the process dynamically as a function of step-type changes in rice husk biomass moisture content and gasifying airflow. To identify stability conditions and the range for inducing disturbances, steady-state tests were carried out using a 32-factorial design. The experimental results demonstrate that within the tested range of airflow, the gasification process operates in the oxygen-limited zone. Despite increasing the airflow from 20 to 40 standard liters per minute (SLPM) and driving the reaction towards the combustion zone, the high temperatures achieved resulted in the gas reaching a peak Lower Heating Value (LHV) of 2.6 MJ/Nm3 and a gas power of 2.6 kW, with a Cold Gas Efficiency (CGE) of 62%. In contrast, the effect of biomass moisture content was negligible due to the thermal inertia of the reactor and the natural variation of the process. Dynamic evaluation revealed that the oxidation temperature and gas concentration were the variables that took the longest to return to stability after air disturbances. It took approximately 1200 s for the hydrogen (H2) concentration to stabilize, while the gas power required about 300 s. No clear results were observed regarding the impact of the dynamic disturbance in moisture content, which varied between 12.3% w.t and 21.5% w.t.

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Patients with diabetes face a 2-4-fold greater cardiovascular risk compared to those without diabetes. Both metformin and acetylsalicylic acid (aspirin) treatment have demonstrated a significant reduction in this risk. This single-center, open-label, sequence randomized, 2 × 2 crossover, single-dose clinical trial evaluated the pharmacokinetics profile and comparative bioavailability of a novel oral fixed-dose combination (FDC) of metformin/acetylsalicylic acid (500/100 mg tablet) versus the reference mono-drugs administered concomitantly, metformin 500 mg tablet and acetylsalicylic acid 100 mg tablet, in 22 healthy Mexican adult volunteers under fasting conditions. Blood samples were collected predose and at specified intervals across a 24-hour period following administration and were analyzed for metformin and salicylic acid using high-performance liquid chromatography coupled with tandem mass spectrometry. Test products were considered to have comparative bioavailability if confidence intervals of natural log-transformed (maximum plasma drug concentration (Cmax), (area under the plasma drug concentration-time curve form 0 up to last sampling time (AUC0 -t), and (area under the plasma drug concentration-time cruve from 0 up to infinity (AUC0 ∞) data were within the range of 80%-125%. The results obtained from the present clinical study demonstrate the comparative bioavailability of the FDC when compared with the coadministration of reference mono-drugs. There were no adverse events or adverse reactions reported throughout the study.

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OBJECTIVES: To investigate artefacts produced by different orthodontic brackets and wires in cone-beam computed tomography (CBCT) scans. MATERIALS AND METHODS: Two dental arches were made using extracted human teeth and plaster. Three pairs of acetate plates containing different brackets - metallic, ceramic, and self-ligating ceramic with NiTi clip - along with a control plate (i.e., without brackets) were prepared. Wire changes (NiTi and steel) were made during CBCT acquisitions, performed with a fixed exposure protocol. Axial slices were selected for mean gray values and standard deviation measurement in three regions of interest (buccal, lingual, and tooth). Noise and contrast-to-noise ratio (CNR) were calculated and compared among the different brackets and wires by ANOVA with a significance level of 5%. RESULTS: Overall, the buccal and tooth region were mostly affected by the metallic and self-ligating brackets, showing higher noise, and lower CNR (p < 0.05). On the other hand, less impact of ceramic brackets in the image quality was observed (p ≥ 0.05). The lingual region did not show expressive differences among the brackets and wire combinations (p ≥ 0.05). The presence of wire associated with the brackets did not worsen image quality (p ≥ 0.05). CONCLUSIONS: In conclusion, metallic and self-ligating brackets have greater artefact expression than ceramic brackets. The wire did not influence image quality. CLINICAL RELEVANCE: One should pay attention to the type of brackets when requesting a CBCT scan during treatment, as metallic and self-ligating brackets may express greater artefacts than ceramic brackets.

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Contamination with traces of pharmaceutical compounds, such as ciprofloxacin, has prompted interest in their removal via low-cost, efficient biomass-based adsorption. In this study, classical models, a mechanistic model, and a neural network model were evaluated for predicting ciprofloxacin breakthrough curves in both laboratory- and pilot scales. For the laboratory-scale (d = 2.2 cm, Co = 5 mg/L, Q = 7 mL/min, T = 18 °C) and pilot-scale (D = 4.4 cm, Co = 5 mg/L, Q = 28 mL/min, T = 18 °C) setups, the experimental adsorption capacities were 2.19 and 2.53 mg/g, respectively. The mechanistic model reproduced the breakthrough data with high accuracy on both scales (R2 > 0.4 and X2 < 0.15), and its fit was higher than conventional analytical models, namely the Clark, Modified Dose-Response, and Bohart-Adams models. The neural network model showed the highest level of agreement between predicted and experimental data with values of R2 = 0.993, X2 = 0.0032 (pilot-scale) and R2 = 0.986, X2 = 0.0022 (laboratory-scale). This study demonstrates that machine learning algorithms exhibit great potential for predicting the liquid adsorption of emerging pollutants in fixed bed.

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Recent progress in out-of-equilibrium closed quantum systems has significantly advanced the understanding of mechanisms behind their evolution toward thermalization. Notably, the concept of nonthermal fixed points (NTFPs)-responsible for the emergence of spatiotemporal universal scaling in far-from-equilibrium systems-has played a crucial role in both theoretical and experimental investigations. In this work, we introduce a differential equation that has the universal scaling associated with NTFPs as a solution. The advantage of working with a differential equation, rather than only with its solution, is that we can extract several insightful properties not necessarily present in the solution alone. How the differential equation is derived allows physical interpretation of the universal exponents in terms of the time dependence of the amplitude of the distributions and their momentum scaling. Employing two limiting cases of the equation, we determined the universal exponents related to the scaling using the distributions near just two momentum values. We established a solid agreement with previous investigations by validating this approach with three distinct physical systems. This consistency highlights the universal nature of scaling due to NTFPs and emphasizes the predictive capabilities of the proposed differential equation. Moreover, under specific conditions, the equation predicts a power-law related to the ratio of the two universal exponents, leading to implications concerning particle and energy transport. This suggests that the observed power-laws in far-from-equilibrium turbulent fluids could be related to the universal scaling due to NTFPs, potentially offering insights into the study of turbulence.

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Although advancements in CAD/CAM technology allow for more personalized treatments, it is not clear how modifications in the CAD/CAM milling process could affect the restoration surface conditions and their mechanical behavior. The objective of this study was to evaluate the effect of different CAD/CAM milling protocols on the topography and fracture behavior of zirconia monolithic crowns (3Y-PSZ) subjected to a chewing simulation. Monolithic 3Y-PSZ premolar crowns were milled using three protocols (n = 13) (slow (S), normal (N), and fast (F)). Crowns were cemented on a dentin analog abutment and subjected to mechanical aging (200 N, 2 Hz, 1,500,000 cycles, 37 °C water). Surviving crowns were subjected to compressive load test and analyzed using fractography. Fracture load data were analyzed with two-parameter Weibull analysis. The surface topography of the crowns was examined with a stereomicroscope and a 3D non-contact profiler. All crowns survived the chewing simulation. Crowns milled using the F protocol had the greatest characteristic fracture load, while crowns produced with the S protocol showed high Weibull modulus. Groups N and S had a more uniform surface and detailed occlusal anatomy than group F. The CAD/CAM milling protocol affected the topography and mechanical behavior of 3Y-PSZ monolithic crowns.

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We developed a mathematical model to simulate dynamics associated with the proliferation of Geobacter and ultimately optimize cellular operation by analyzing the interaction of its components. The model comprises two segments: an initial part comprising a logistic form and a subsequent segment that incorporates acetate oxidation as a saturation term for the microbial nutrient medium. Given that four parameters can be obtained by minimizing the square root of the mean square error between experimental Geobacter growth and the mathematical model, the model underscores the importance of incorporating nonlinear terms. The determined parameter values closely align with experimental data, providing insights into the mechanisms that govern Geobacter proliferation. Furthermore, the model has been transformed into a scaleless equation with only two parameters to simplify the exploration of qualitative properties. This allowed us to conduct stability analysis of the fixed point and construct a co-dimension two bifurcation diagram.

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This study aimed to evaluate the effects of different doses of equine chorionic gonadotropin (eCG; 200 and 300 IU) administered at the end of a fixed-time artificial insemination (FTAI) treatment protocol on ovulation, pregnancy, and twin rates in Bos taurus beef heifers. In addition, pregnancy losses in heifers with singleton and twin pregnancies were determined. A total of 2382 Angus heifers treated with a 6-day estradiol/progesterone-based protocol for FTAI (J-Synch protocol) were randomly allocated to two experimental groups to receive 200 or 300 IU of eCG administered intramuscularly at the time of intravaginal progesterone device removal; FTAI was performed from 60 to 72 h after device removal. The pregnancy rate did not differ (P = 0.89) between the 200 and 300 IU eCG groups. The number of corpus luteum induced by both eCG doses was determined by ultrasonographic examination 14 days after insemination and those treated with 300 IU of eCG had a greater double ovulation rate (P < 0.05). In addition, 300 IU eCG treated heifers had a higher twinning rate on day 30 of gestation (P < 0.05) and parturition (P < 0.05). Pregnancy losses from 30 days of gestation to calving did not differ between heifers treated with 200 and 300 IU of eCG (P = 0.70). However, regardless of the experimental group, heifers bearing twins had greater pregnancy losses than heifers with singletons (P < 0.05). In conclusion, reducing the dose of eCG from 300 to 200 IU under FTAI treatment protocol decreases double ovulation and twinning rates, maintaining a similar pregnancy rate in heifers. Nulliparous cows carrying two fetuses suffer greater pregnancy losses than cows with singletons.

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The aim of this study was to evaluate the effectiveness of motivational interviewing on improving oral hygiene behavior in patients with fixed orthodontics appliances. A parallel-group randomized clinical trial was conducted with 45 patients of the Orthodontic Clinic of Unibe's Postgraduate Unit. A computer-generated list of numbers created with SPSS V21.0 was used to randomly allocate participants into the experimental or the control group. Monthly oral hygiene instructions and an oral hygiene kit from GUM® with special orthodontic hygiene tools were given to the participants. Furthermore, the experimental group underwent motivational interviewing sessions facilitated by a periodontist who received training from two expert psychologists. These psychologists also provided supervision to the interviewer, ensuring the accurate implementation of the intervention. Simplified Oral Hygiene Index (SOHI), Gingival Index (GI), Periodontal Probing Depth (PPD) and Bleeding on Probing (BoP) were recorded at baseline, three and six months after the beginning of the study. The participant and the evaluator (another periodontist who recorded the data) were masked. Repeated-measures mixed- model analysis of variance and chi-squared test were conducted. Mean SOHI, GI, PPD and BoP scores did not differ significantly across the three time points (baseline, three and six months). Nevertheless, a significant interaction on SOHI scores (F (2, 58) = 3.463, p = .038, h2 = .052) was found between the sessions and the treatment conditions (experimental vs control group) at the third and sixth month. Motivational interviewing plus oral hygiene instructions appears to maintain a better control of dental biofilm and calculus in comparison with conventional oral hygiene instructions alone.

El objetivo de este trabajo fue evaluar la efectividad de las entrevistas motivacionales para mejorar el comportamiento de higiene oral en pacientes con aparatos ortodóncicos fijos. Se llevó a cabo un ensayo clínico aleatorizado de grupos paralelos con 45 pacientes de la Clínica de Ortodoncia de la Unidad de Posgrado de Unibe. Se utilizó una lista de números generada por computadora con SPSS V21.0 para asignar aleatoriamente a los participantes al grupo experimental o de control. Se les proporcionó a los participantes instrucciones mensuales de higiene oral y un kit de higiene oral de GUM® con utensilios de higiene especiales para ortodoncia. Además, el grupo experimental recibió sesiones de entrevista motivacional facilitadas por un periodoncista capacitado por dos psicólogas expertas. Estas psicólogas también supervisaron al entrevistador, asegurando la implementación precisa de la intervención. Se registró el Índice Simplificado de Higiene Oral (IHO-S), el Índice Gingival (IG), la Profundidad de Sondaje Periodontal (PS) y el Sangrado al Sondaje (SS) al inicio, a los tres y seis meses después del inicio del estudio. Tanto el participante como el evaluador (otro periodoncista que registró los datos) estaban enmascarados. Se realizaron análisis de varianza de medidas repetidas con modelo mixto y pruebas de chi-cuadrado. Las puntuaciones medias del IHO-S, IG, PS y SS no difirieron significativamente en los tres momentos (inicio, tres y seis meses). Sin embargo, se encontró una interacción significativa en las puntuaciones del IHO-S (F (2, 58) = 3.463, p = .038, h2 = .052) entre las sesiones y las condiciones de tratamiento (grupo experimental vs grupo de control) en el tercer y sexto mes. Las entrevistas motivacionales junto con las instrucciones de higiene oral parecen mantener un mejor control de la biopelícula dental y el cálculo en comparación con las instrucciones convencionales de higiene oral por sí solas.

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Biological production and outgassing of greenhouse gasses (GHG) in Eastern Boundary Upwelling Systems (EBUS) are vital for fishing productivity and climate regulation. This study examines temporal variability of biogeochemical and oceanographic variables, focusing on dissolved oxygen (DO), nitrate, nitrogen deficit (N deficit), nitrous oxide (N2O) and air-sea N2O flux. This analysis is based on monthly observations from 2000 to 2023 in a region of intense seasonal coastal upwelling off central Chile (36°S). Strong correlations are estimated among N2O concentrations and N deficit in the 30-80 m layer, and N2O air-sea fluxes with the proportion of hypoxic water (4 < DO < 89 µmol L-1) in the water column, suggesting that N2O accumulation and its exchange are mainly associated with partial denitrification. Furthermore, we observe interannual variability in concentrations and inventories in the water column of DO, nitrate, N deficit, as well as air-sea N2O fluxes in both downwelling and upwelling seasons. These variabilities are not associated with El Niño-Southern Oscillation (ENSO) indices but are related to interannual differences in upwelling intensity. The time series reveals significant nitrate removal and N2O accumulation in both mid and bottom layers, occurring at rates of 1.5 µmol L-1 and 2.9 nmol L-1 per decade, respectively. Particularly significant is the increase over the past two decades of air-sea N2O fluxes at a rate of 2.9 µmol m-2 d-1 per decade. These observations suggest that changes in the EBUS, such as intensification of upwelling and the prevalence of hypoxic waters may have implications for N2O emissions and fixed nitrogen loss, potentially influencing coastal productivity and climate.

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This study evaluated the efficiency of prostaglandin F2α (PGF) to hasten ovulation in weaned sows. In experiment I, weaned sows detected in estrus (0 h) received: no hormone (Control; n = 56); 0.5 mg PGF IM at 0 h and 2 h (PGF0; n = 56); or 0.5 mg PGF IM at 24 h and 26 h (PGF24; n = 55). In experiment II, weaned sows that did not express estrus signs until 72 h after weaning (0 h) were assigned to: no hormone (Control; n = 45); 10 µg buserelin acetate IM at 0 h (Buserelin; n = 43); 0.5 mg PGF IM at 34 h and 36 h (PGF; n = 44); or 10 µg buserelin acetate IM at 0 h plus 0.5 mg PGF IM at 34 h and 36 h (Buserelin + PGF; n = 45). In experiment I, no effect of PGF on the interval treatment onset to ovulation was observed (P > 0.05), and no treatment effect was observed on the relative or cumulative proportion of females that ovulated post-treatment onset (P > 0.05). In experiment II, treatment onset to ovulation interval was shorter for Buserelin group than for PGF group (P < 0.05), and a higher cumulative percentage of Buserelin treated sows ovulated up to 48 h compared to PGF and Control groups (P < 0.01), with no differences from Buserelin + PGF. Treatments did not affect total number of piglets born in both experiments (P > 0.05). In conclusion, PGF did not hasten ovulation timing or affect litter size in weaned sows.

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INTRODUCTION: one- or two-stage total revision is considered the gold standard for the treatment of hip arthroplasty with chronic infection. However, during the removal of a fixed prosthetic component, the host bone may be damaged, making definitive prosthetic reimplantation difficult. OBJECTIVE: we present a series of patients treated for chronic periprosthetic hip infection with preservation of one fixed component. MATERIAL AND METHODS: this study included 12 patients with hip arthroplasty and chronic periprosthetic infection scheduled for one or two-stage partial replacement with retention of a fixed component between June 2015 and January 2021. The minimum follow-up period was 2 years (mean, 4.08 years). None of the 12 patients in this series was lost to follow-up. We evaluated the evolution through clinical examination, Harris Hip Score, laboratory and radiological studies. RESULTS: at a mean follow-up of 4.08 years after prosthetic reimplantation, two of the 12 patients had recurrence of infection (16.6%), and the mean Harris hip score reached 63.6 points at the last follow-up assessment. CONCLUSIONS: fixed implant preservation may be an acceptable option for patients with chronic periprosthetic hip infection when removal of the fixed component results in significant bone loss compromising future reimplantation. However, more studies are required on this treatment method.

INTRODUCCIÓN: la revisión total en una o dos etapas se considera el estándar de oro para el tratamiento de la artroplastía de cadera con infección crónica. Sin embargo, durante la extracción de un componente protésico fijo, el hueso del huésped puede dañarse, lo que dificulta la reimplantación definitiva de la prótesis. OBJETIVO: presentamos una serie de pacientes tratados por infección crónica periprotésica de cadera con la preservación de un componente fijo. MATERIAL Y MÉTODOS: este estudio retrospectivo incluyó a 12 pacientes con artroplastía de cadera e infección periprotésica crónica programadas para revisión parcial en una o dos etapas con retención de un componente fijo entre Junio de 2015 y Enero de 2021. El período mínimo de seguimiento fue de dos años (media, 4.08 años). Ninguno de los 12 pacientes de esta serie se perdió en el seguimiento. Evaluamos la evolución a través del examen clínico, puntuación de cadera de Harris, estudios de laboratorio y radiológicos. RESULTADOS: con un seguimiento promedio de 4.08 años después de la reimplantación protésica, dos de los 12 pacientes presentaron recurrencia de la infección (16.6%) y la puntuación media de Harris en la cadera alcanzó 63.6 puntos en la última evaluación de seguimiento. CONCLUSIONES: la preservación del implante fijo puede ser una opción aceptable para pacientes estrictamente seleccionados con infección periprotésica crónica de cadera cuando la extracción del componente fijo produce una pérdida ósea significativa que compromete la reconstrucción futura. Se necesitan más estudios sobre este método de tratamiento.

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One prominent aspect of Parkinson's disease (PD) is the presence of elevated levels of free radicals, including reactive oxygen species (ROS). Syagrus coronata (S. coronata), a palm tree, exhibits antioxidant activity attributed to its phytochemical composition, containing fatty acids, polyphenols, and flavonoids. The aim of this investigation was to examine the potential neuroprotective effects of S. coronata fixed oil against rotenone-induced toxicity using Drosophila melanogaster. Young Drosophila specimens (3-4 d old) were exposed to a diet supplemented with rotenone (50 µM) for 7 d with and without the inclusion of S. coronata fixed oil (0.2 mg/g diet). Data demonstrated that rotenone exposure resulted in significant locomotor impairment and increased mortality rates in flies. Further, rotenone administration reduced total thiol levels but elevated lipid peroxidation, iron (Fe) levels, and nitric oxide (NO) levels while decreasing the reduced capacity of mitochondria. Concomitant administration of S. coronata exhibited a protective effect against rotenone, as evidenced by a return to control levels of Fe, NO, and total thiols, lowered lipid peroxidation levels, reversed locomotor impairment, and enhanced % cell viability. Molecular docking of the oil lipidic components with antioxidant enzymes showed strong binding affinity to superoxide dismutase (SOD) and glutathione peroxidase (GPX1) enzymes. Overall, treatment with S. coronata fixed oil was found to prevent rotenone-induced movement disorders and oxidative stress in Drosophila melanogaster.

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INTRODUCTION: The aim of this study was to assess the interaction between a 0.019×0.025-inch (″) stainless steel archwire and two types of passive self-ligating brackets with the same slot height (0.022″) and different slot depths (0.028″ and 0.026″, and to measure the archwire/slot play as well as to compare the torque expression with archwire torsions of 12°, 24°, and 36°. MATERIAL AND METHODS: An experimental device was developed along with a universal testing machine to measure torque expression in two types of brackets with 0.028″ and 0.026″ slot depths. Analysis of variance (ANOVA) and Tukey's test were performed to identify the differences between groups. RESULTS: The 0.026″ slot bracket presented greater archwire/slot play when compared to the 0.028″ bracket. Torque expression with torsions of 24° and 36° were significantly higher in the 0.028″ depth brackets when compared to the 0.026″ depth brackets. CONCLUSION: The 0.022″×0.026″ passive self-ligating brackets attached with a 0.019″×0.025″ stainless steel archwire provided no greater torque control when compared to 0.022″×0.028″ passive self-ligating brackets.

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BACKGROUND: Patients experiencing any malocclusion, may desire for treatment. However, there is no scientific information orthodontic treatment demand and the knowledge of young adults about orthodontic treatment. The aim of the study was to assess orthodontic treatment demand in young adults from Poland and Chile, their previous orthodontic experience and their knowledge on fixed and aligner orthodontic treatment. METHODS: The target group comprised people aged 18-30. The sample size was estimated as above 400 for each country. The survey was carried out in Polish and Spanish within 3 months and consisted of 25 questions delivered via social media. Comparisons were made between countries, age subgroups and gender. RESULTS: The response rate was 1,99%, what stands for 1092 responses, 670 from Chile and 422 from Poland, respectively. The percentage of young adults who were already treated was 42,9% in Poland and 25,0% in Chile. The ones planning to have orthodontic treatment within a year counted for 11,8% in Poland and 5,3% in Chile. Most young adults who want to be treated (20,6%) rely on doctor's recommendation on type of appliance while 14,7% of all respondents are interested solely in aligners. Most respondents have heard about aligners (58%). Direct provider-to-customer service without a doctor is not acceptable, neither in Poland (85,1%) nor in Chile (64,8%). Most young adults provided incorrect answers referring various aspects of aligner treatment. CONCLUSIONS: In both countries, patients demand to be treated and monitored by the orthodontist. A high percentage of patients want to be treated exclusively with aligners. Direct-to-consumer orthodontics does not seem attractive to patients. Young adults do not have adequate knowledge referring to aligner treatment. Many people want to be treated despite a previous orthodontic treatment.

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In this work, the adsorption of nickel ions from a real effluent from a metal-mechanic industry was investigated in a fixed-bed column using biochar. Biochar was prepared from winemaking residues originating from the Beifiur® composting process. The use of wine industry residues as precursor materials for biochar production is established in biomass residue valorization using the existing logistics and the lowest possible number of manipulations and pre-treatments. The results found in the work showed that the optimal conditions for nickel adsorption in fixed-bed columns were bed height (Z) of 7 cm, initial nickel concentration (C0) of 1.5 mg L-1, and flow rate (Q) of 18 mL min-1. In this condition, the maximum adsorption capacity of the column was 0.452 mg g-1, the mass transfer zone (Zm) was 3.3 cm, the treated effluent volume (Veff) was 9.72 L, and the nickel removal (R) was 92.71%. The Yoon-Nelson and BDST dynamic models were suitable to represent the breakthrough curves of nickel adsorption. Finally, the fixed-bed column adsorption using biochar from winemaking residues proved to be a promising alternative for nickel removal from real industrial effluents.

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OBJECTIVE: The aim of this study is to assess the microbial contamination of three different brands of esthetic elastomeric ligatures. MATERIALS AND METHODS: Different brands of esthetic ligatures (Unistick Pearl [American Orthodontics, Sheboygan, WI, USA], Power Sticks Pearl [Ortho Technology, Tampa, FL, USA], and Ease [Obscure, 3M Unitek, Monrovia, CA, USA]) were randomly assigned to permanent canines of 25 patients (aged 11-18 years) undergoing corrective orthodontic treatment. After 30 days, the ligatures were removed, processed, and the biofilm composition was analyzed by checkerboard DNA-DNA hybridization for 40 bacterial species. The microbiological data were analyzed using a nonparametric mixed model. RESULTS: The ligatures presented intense microbial contamination after 30 days, but no statistically significant differences were observed among the three groups (p > 0.05). The levels of the evaluated individual species and proportions of the microbial complexes showed no statistically significant differences among the ligature groups (p > 0.05). CONCLUSIONS: Esthetic elastomeric ligatures became multicolonized by several bacterial species after 30 days of exposure to the oral cavity. However, no relevant differences were observed among the biofilm composition formed on the different ligature brands.

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The choice of retaining material that will replace the lost properties of the tooth, in which it is fragile and with loss of dentin structure, is important. The success of the treatment will depend on the qualities presented in it. Therefore, the objective of this work, through a literature review, is to present the advantages and disadvantages observed in the use of fiberglass post intraradicular retainer. This paper reviews the most relevant articles on the specificities presented in the fiberglass post retaining material, published in the period (2003 to 2020). The bibliographic search was performed in PubMed, Lilacs, Scielo, Google Scholar databases. In view of the selected articles on the subject, it is possible to observe the authors' acceptance of the application of the use of retainers, highlighting that in the treatment of cases with extensive coronary destruction, the aim is to have the functional and retentive capacity returned, in addition to the tension resistance. Therefore, theThe use of fiberglass posts in weakened teeth is effective as the material of choice. In cases that require reconstruction and return of tissue integrity, it has sufficient advantages for its selection. Despite the disadvantages it has, these do not outweigh the benefits to the point of making its use unfeasible. However, knowing when, where and how to treat is always important in any procedure for a satisfactory final outcome.

A escolha do material retentor que irá substituir as propriedades perdidas do dente, no qual este se apresenta de forma fragilizada e com perca de estrutura dentinária é importante. O sucesso do tratamento irá depender das qualidades apresentadas no mesmo. Sendo assim, o objetivo deste trabalho por meio de uma revisão de literatura é apresentar as vantagens e desvantagens observadas no uso do retentor intrarradicular de pino de fibra de vidro. Este trabalho revisa os artigos mais relevantes sobre as especificidades apresentadas no material retentor de pino de fibra de vidro, publicadas no período (2003 até 2020). A busca bibliográfica foi realizada nos bancos de dados PubMed, Lilacs, Scielo, Google Scholar. Diante dos artigos selecionados referentes ao tema, pode-se observar a aceitação dos autores sobre a aplicação do uso de retentores, destacando-se que no tratamento de casos com destruição coronária extensa o intuito é dispor da devolução da capacidade funcional, retentiva, além da resistência a tensão. Portanto, a utilização de pinos de fibra de vidro em dentes fragilizados apresenta efetividade como material de escolha. Em casos que necessitam de reconstrução e devolução de sua integridade tecidual, possui consigo vantagens suficientes para sua seleção. Apesar das desvantagens que possui, essas não se sobrepõem aos benefícios a ponto de tornarem inviáveis ao seu uso. Entretanto, saber quando, onde e como tratar é sempre importante em qualquer procedimento para um desfecho final satisfatório.

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