Interaction of sakuranetin with unsaturated lipids forming Langmuir monolayers at the air-water interface: A biomembrane model.

This study investigates the interaction between sakuranetin, a versatile pharmaceutical flavonoid, and monolayers composed of unsaturated phospholipids, serving as a surrogate for cell membranes. The phospholipids were 1-palmitoyl-2-oleoyl-glycero-3-phosphocholine (POPC) and 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine (POPE). We conducted a series of experiments to comprehensively investigate this interaction, including surface pressure assessments, Brewster angle microscopy (BAM), and polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS). Our findings unequivocally demonstrate that sakuranetin interacts with these phospholipids, expanding the monomolecular films. Notably, regarding POPC, the presence of sakuranetin led to a reduction in stability and a decline in surface elasticity, which can likely be attributed to intricate molecular rearrangements at the interface. The visual evidence of aggregations in BAM images reinforces the interactions substantiated by PM-IRRAS, highlighting sakuranetin's interaction with the polar and nonpolar regions of POPC. However, it is worth noting that these aggregations do not appear to contribute significantly to the viscosity of the mixed film, and our investigations did not reveal any substantial hysteresis. In contrast, when examining POPE, we observed a minor reduction in thermodynamic stability, indicative of fewer rearrangements within the monolayer. This notion was further reinforced by the limited presence of aggregations in the BAM images. Sakuranetin also increased the rigidity of the lipid monolayer; nevertheless, the monolayer remained predominantly elastic, facilitating easy re-spreading on the surface, especially for the first lipid. PM-IRRAS analysis unveiled interactions between sakuranetin and POPE's polar and nonpolar segments, compellingly explaining the observed monolayer expansion. Taken together, our data suggest that sakuranetin was more effectively incorporated into the monomolecular layer of POPE, indicating that membranes comprised of POPC might exhibit a greater degree of interaction in the presence of this pharmacologically active compound.

Impact of vertical positioning on lung aeration among mechanically ventilated intensive care unit patients: a randomized crossover clinical trial / Impacto do posicionamento vertical na aeração pulmonar em pacientes de unidades de terapia intensiva ventilados mecanicamente: um estudo clínico transversal randomizado

ABSTRACT Objective: To assess the impact of different vertical positions on lung aeration in patients receiving invasive mechanical ventilation. Methods: An open-label randomized crossover clinical trial was conducted between January and July 2020. Adults receiving invasive mechanical ventilation for > 24 hours and < 7 days with hemodynamic, respiratory and neurological stability were randomly assigned at a 1:1 ratio to the sitting position followed by passive orthostasis condition or the passive orthostasis followed by the sitting position condition. The primary outcome was lung aeration assessed using the lung ultrasound score (score ranges from 0 [better] to 36 [worse]). Results: A total of 186 subjects were screened; of these subjects, 19 were enrolled (57.8% male; mean age, 73.2 years). All participants were assigned to receive at least one verticalization protocol. Passive orthostasis resulted in mean lung ultrasound scores that did not differ significantly from the sitting position (11.0 versus 13.7; mean difference, -2.7; [95%CI -6.1 to 0.71; p = 0.11). Adverse events occurred in three subjects in the passive orthostasis group and in one in the sitting position group (p = 0.99). Conclusion: This analysis did not find significant differences in lung aeration between the sitting and passive orthostasis groups. A randomized crossover clinical trial assessing the impact of vertical positioning on lung aeration in patients receiving invasive mechanical ventilation is feasible. Unfortunately, the study was interrupted due to the need to treat COVID-19 patients. ClinicalTrials.gov registry: NCT04176445

RESUMO Objetivo: Avaliar o impacto de diferentes posicionamentos verticais na aeração pulmonar em pacientes em ventilação mecânica invasiva. Métodos: Trata-se de ensaio clínico aberto, randomizado e transversal, realizado entre janeiro e julho de 2020. Adultos em ventilação mecânica invasiva por mais de 24 horas e menos de 7 dias com estabilidade hemodinâmica, respiratória e neurológica foram distribuídos aleatoriamente em uma proporção de 1:1 à postura sentada seguida da condição de ortostatismo passivo ou o ortostatismo passivo seguido de postura sentada. O desfecho primário foi a aeração pulmonar avaliada pelo lung ultrasound score. O escore varia de zero (melhor) a 36 (pior). Resultados: Foram selecionados 186 indivíduos; destes, 19 foram incluídos (57,8% do sexo masculino; média idade de 73,2 anos). Todos os participantes foram selecionados para receber pelo menos um protocolo de verticalização. O ortostatismo passivo resultou em escores médios de aeração pulmonar por ultrassonografia que não diferiram significativamente da postura sentada (11,0 versus 13,7; diferença média, -2,7; IC95% -6,1 a 0,71; p = 0,11). Ocorreram eventos adversos em três indivíduos no grupo ortostatismo passivo e em um no grupo postura sentada (p = 0,99). Conclusão: Esta análise não encontrou diferenças significativas na aeração pulmonar entre os grupos ortostatismo passivo e postura sentada. É factível conduzir um estudo clínico transversal randomizado para avaliar o impacto do posicionamento vertical na aeração pulmonar em pacientes em ventilação mecânica invasiva. Infelizmente, o estudo foi interrompido devido à necessidade de tratar pacientes com COVID-19. Registro ClinicalTrials.gov: NCT04176445

Unsaturation pattern of phosphatidylglycerols modulating the interaction of lysicamine with cells membrane models at the air-water interface.

Lysicamine, an alkaloid with tumorigenic activity, was incorporated in cell membrane models made of lipid Langmuir monolayers. Dipalmitoylphosphocholine (DPPC), dioleoylphosphocholine (DOPC), and palmitoyloleoylcholine (POPC) represented non-tumorigenic cell membranes, and dipalmitoylphosphoserine (DPPS), dioleoylphosphoserine (DOPS), and palmitoyloleoylserine (POPS), tumorigenic ones. The monolayers were characterized by tensiometry, infrared spectroscopy, and Brewster Angle Microscopy (BAM). No significant shifts of the isotherms were observed for the saturated lipids (DPPC and DPPS), while for the others (DOPC, POPS, DOPS, and POPS), more significant changes were observed not only in the compression isotherms but also in the surface pressure-time curve for pre-compressed monolayers. The molecular organization, as well as the morphology of the drug-lipid monolayers, could be inferred with infrared spectroscopy and BAM. While the first revealed that the alkyl chain ordering changed upon lysicamine incorporation, the second showed how the drug could distinctly change the state of aggregation of molecular domains at the air-water interface. In conclusion, lysicamine could interact distinctly with each lipid at the air-water interface, showing the dependence not only on the lipid polar groups but also on the level of unsaturation of the alkyl chains.

The composition of fusogenic lipid mixtures at the air-water modulates the physicochemical properties changes upon interaction with lysicamine.

Knowing how a bioactive compound interacts with cell membranes is important to understand its effect at the molecular level. In this sense, this work aimed to study the interaction of lysicamine, an alkaloid with action against lung cancer cell lines, with lipid monolayers as cell membrane models. We employed two lipid mixtures: the first composed of 35% DOPC, 30% DOPE, 20% sphingomyelin, and 15% cholesterol as healthy cell membranes models (MM1), and the second replacing DOPC with DOPS as cancer cells models (MM2). The interaction of lysicamine with the monolayers was evaluated using tensiometry, Brewster angle microscopy (BAM), and polarization-modulated infrared reflection-absorption spectroscopy (PM-IRRAS). Lysicamine had interfacial effects in both membrane models. For MM 1, it expanded the lipid monolayer and changed the interfacial rheological properties, increasing the in-plane elasticity of the films. PM-IRRAS spectra suggested a higher conformational disorder of the alkyl chains of the lipids. For MM 2, lysicamine also shifted the isotherms to higher areas, expanding the monolayers, but with no significant alteration in their interfacial rheological properties. PM-IRRAS spectra also suggested higher disorder in the orientation of the lipid alkyl chains upon lysicamine incorporation. For both models, BAM did not show alteration in interfacial aggregation upon drug incorporation. In conclusion, changes in some interfacial properties of membrane models caused by lysicamine depend on the monolayer composition, which can be associated with its bioactivity in cellular membranes.

Impact of vertical positioning on lung aeration among mechanically ventilated intensive care unit patients: a randomized crossover clinical trial.

OBJECTIVE: To assess the impact of different vertical positions on lung aeration in patients receiving invasive mechanical ventilation. METHODS: An open-label randomized crossover clinical trial was conducted between January and July 2020. Adults receiving invasive mechanical ventilation for > 24 hours and < 7 days with hemodynamic, respiratory and neurological stability were randomly assigned at a 1:1 ratio to the sitting position followed by passive orthostasis condition or the passive orthostasis followed by the sitting position condition. The primary outcome was lung aeration assessed using the lung ultrasound score (score ranges from 0 [better] to 36 [worse]). RESULTS: A total of 186 subjects were screened; of these subjects, 19 were enrolled (57.8% male; mean age, 73.2 years). All participants were assigned to receive at least one verticalization protocol. Passive orthostasis resulted in mean lung ultrasound scores that did not differ significantly from the sitting position (11.0 versus 13.7; mean difference, -2.7; [95%CI -6.1 to 0.71; p = 0.11). Adverse events occurred in three subjects in the passive orthostasis group and in one in the sitting position group (p = 0.99). CONCLUSION: This analysis did not find significant differences in lung aeration between the sitting and passive orthostasis groups. A randomized crossover clinical trial assessing the impact of vertical positioning on lung aeration in patients receiving invasive mechanical ventilation is feasible. Unfortunately, the study was interrupted due to the need to treat COVID-19 patients.ClinicalTrials.gov registry: NCT04176445.

IMPACTO-MR: um estudo brasileiro de plataforma nacional para avaliar infecções e multirresistência em unidades de terapia intensiva / IMPACTO-MR: a Brazilian nationwide platform study to assess infections and multidrug resistance in intensive care units

RESUMO Objetivo: Descrever o IMPACTO-MR, um estudo brasileiro de plataforma nacional em unidades de terapia intensiva focado no impacto das infecções por bactérias multirresistentes relacionadas à assistência à saúde. Métodos: Descrevemos a plataforma IMPACTO-MR, seu desenvolvimento, critérios para seleção das unidades de terapia intensiva, caracterização da coleta de dados, objetivos e projetos de pesquisa futuros a serem realizados na plataforma. Resultados: Os dados principais foram coletados por meio do Epimed Monitor System® e consistiram em dados demográficos, dados de comorbidades, estado funcional, escores clínicos, diagnóstico de internação e diagnósticos secundários, dados laboratoriais, clínicos e microbiológicos e suporte de órgãos durante a internação na unidade de terapia intensiva, entre outros. De outubro de 2019 a dezembro de 2020, 33.983 pacientes de 51 unidades de terapia intensiva foram incluídos no banco de dados principal. Conclusão: A plataforma IMPACTO-MR é um banco de dados clínico brasileiro de unidades de terapia intensiva focado na pesquisa do impacto das infecções por bactérias multirresistentes relacionadas à assistência à saúde. Essa plataforma fornece dados para o desenvolvimento e pesquisa de unidades de terapia intensiva individuais e ensaios clínicos observacionais e prospectivos multicêntricos.

ABSTRACT Objective: To describe the IMPACTO-MR, a Brazilian nationwide intensive care unit platform study focused on the impact of health care-associated infections due to multidrug-resistant bacteria. Methods: We described the IMPACTO-MR platform, its development, criteria for intensive care unit selection, characterization of core data collection, objectives, and future research projects to be held within the platform. Results: The core data were collected using the Epimed Monitor System® and consisted of demographic data, comorbidity data, functional status, clinical scores, admission diagnosis and secondary diagnoses, laboratory, clinical, and microbiological data, and organ support during intensive care unit stay, among others. From October 2019 to December 2020, 33,983 patients from 51 intensive care units were included in the core database. Conclusion: The IMPACTO-MR platform is a nationwide Brazilian intensive care unit clinical database focused on researching the impact of health care-associated infections due to multidrug-resistant bacteria. This platform provides data for individual intensive care unit development and research and multicenter observational and prospective trials.

Critical Analysis of The Changes in CFM Resolution 2294/21 And Its Impacts on Assisted Human Reproduction.

The Brazilian Federal Board of Medicine (CFM) issued resolution number 2294/21, which regulates human reproduction procedures in Brazil, bringing significant changes to clinical practice in assisted human reproduction, and it raised ethical, bioethical, and legal discussions between professionals and patients. This study aims to analyze these changes in different aspects, especially because some of them are controversial. Evidence-based knowledge resources were used to support the analyses of crucial points that were impacted by this change. A literature review was carried out to obtain information about guidelines and laws, as well as articles that contemplate ethical discussions on assisted reproduction. The search sites used were BVS, Pub Med, LILACS and Google Scholar. The keywords used were law, legislation, bioethics, reference guide and assisted human reproduction. Relevant official documents from the Brazilian State were also found and included in the survey. The new resolution regarding the use of assisted reproduction techniques brought important changes, with clinical implications for couples who wish to become pregnant, and there is a need for a broad discussion concerning these repercussions from clinical, ethical, bioethical, and legal points of view.

Ethical and bioethical aspects concerning the disclosure of medical information for a fair reason.

OBJECTIVE: The objective of this study was to emphasize the importance of legal and bioethical knowledge in maintaining medical confidentiality, especially in situations when there is a diagnosis of HIV infection. METHODS: A literature review of studies published in the Scientific Electronic Library Online and National Library of Medicine databases was performed. Sixteen studies available in full, online, and free, published between 2010 and 2020, were selected. RESULTS: The studies highlighted that, despite the ethical duty to breach confidentiality for the protection of third parties, many doctors are reluctant to reveal this secret due to the power of stigmatization and social discrimination related to the diagnosis of HIV infection, which affects integrity, counseling, and capability to treat patients. CONCLUSION: HIV diagnosis implies bioethical and legal questions. Respect for medical confidentiality is a matter to be discussed, as there is a need to protect the privacy of the patient, at the same time the responsibility to preserve the health of others.

Ethical and bioethical aspects concerning the disclosure of medical information for a fair reason

SUMMARY OBJECTIVE: The objective of this study was to emphasize the importance of legal and bioethical knowledge in maintaining medical confidentiality, especially in situations when there is a diagnosis of HIV infection. METHODS: A literature review of studies published in the Scientific Electronic Library Online and National Library of Medicine databases was performed. Sixteen studies available in full, online, and free, published between 2010 and 2020, were selected. RESULTS: The studies highlighted that, despite the ethical duty to breach confidentiality for the protection of third parties, many doctors are reluctant to reveal this secret due to the power of stigmatization and social discrimination related to the diagnosis of HIV infection, which affects integrity, counseling, and capability to treat patients. CONCLUSION: HIV diagnosis implies bioethical and legal questions. Respect for medical confidentiality is a matter to be discussed, as there is a need to protect the privacy of the patient, at the same time the responsibility to preserve the health of others.

The use of thymol, carvacrol and sorbic acid in microencapsules to control Salmonella Heidelberg, S. Minnesota and S. Typhimurium in broilers.

Introduction: The control of Salmonella spp. in poultry involves different biosecurity actions and lately has been complicated by the emergence of multidrug resistant serovars. The application of organic acids and essential oils has been used with different approaches due to the antibacterial properties as food preservatives. The use of these molecules in animal feed to control enteric pathogens is a major interest within the poultry industry. Methods: The use of a blend containing nature-identical compounds of sorbic acid (25%), thymol (9.5%) and carvacrol (2.5%) microencapsulated in a lipid matrix, was investigated in the present work, for the control of three Salmonella serovars (S. ser. Typhimurium, S. ser. Heidelberg and S. ser. Minnesota). Commercial broilers were challenged at 3 or at 33 days of age. Groups SH-1, SM-1 and ST-1, received treatment in the feed, at 2 kg/ton from 1-21 days of age and at 1 kg/ton from 35-42 days of age (last week), while groups SH-2, SM-2 and ST-2, were treated only during the last week receiving 2 kg/ton. Each treated group had an untreated control group, that was challenged at the same moment with the respective serovar (groups PCH, PCM and PCT). The challenge strains were enumerated in liver and cecal contents, weekly after challenge, at 7, 14, 21, 28, 35 and 42 days-of-age. Results and discussion: Significant reduction was noticed at 7 and 14 days of age in all groups that received treatment during the initial phase (p < 0.05). Moreover, the body weight was significantly higher at the last experimental day (p < 0.05) in chickens that received treatment at the initial and at the final growth stages.

Orthodontists' preferences regarding the difference of bracket bonding height between the maxillary incisors.

INTRODUCTION: The vertical position of orthodontic brackets in maxillary incisors may influence the incisal step between the anterior teeth and thereby interfere with the smile esthetics. Even so, esthetic standards have been modified over time and consistently required technical adjustments. OBJECTIVE: This study analyzed orthodontists' preferences regarding the difference of bracket bonding height between the maxillary central incisors (MCI) and maxillary lateral incisors (MLI), and further determined whether the orthodontist sex, age and time of specialization have association to their choices. METHODS: This study collected data through an electronic form. Study participants analyzed a clinical case in which they indicated their preference for bracket bonding height. The placement height options ranged from 3.0 mm to 5.5 mm from the incisal edge, with 0.5-mm intervals, or at the clinical crown center (CCC). The difference in the bonding height between the MCI and MLI was analyzed, considering the formation of incisal steps between these teeth. RESULTS: Participants indicated that the difference in bracket bonding height between the MCI and MLI should be as follows: 0 mm (3.9%); 0.5 mm (78.3%); 1 mm (7.6%); 1.5 mm (0.2%); and CCC (9.9%). There was no statistically significant correlation between the choice for bracket bonding height and sex, age and time since specialization. CONCLUSION: Most participating orthodontists choose the 0.5-mm difference in bracket placement height between the MCI and MLI. The variables sex, age and time since specialization did not influence this choice.

Evaluation of the bio-drying process of municipal solid waste using rotating drums Bio-drying rotary drum.

Most of the municipal solid waste collected is disposed of in landfills and controlled landfills. However, efficient ways of recovering these wastes have emerged, such as bio-drying. This technique uses the exothermic degradation reaction of organic matter carried out by microorganisms along with aeration to reduce the moisture of the waste. The objective of the research was to test the bio-drying technique in a rotary drum. For this purpose, three rotary drums were built, and the tested residue was synthetically produced. The aeration rate tested was 1 liter per kilogram per minute, and rotation was performed for one minute every three hours. The analyses performed on the residues were moisture content, volatile solids, calorific value, particle size, and temperature profile. The residues entered the bio-drying process with a moisture content of 52%, 49%, and 54% and went out with 15%, 13%, and 10% for drum 1, 2, and 3, respectively, a reduction of more than 70%. The calorific value increased by 95%, 88%, and 122% for drum 1, 2, and 3, respectively. During the process, no leachate generation was observed.

Repetitive Peripheral Sensory Stimulation as an Add-On Intervention for Upper Limb Rehabilitation in Stroke: A Randomized Trial.

INTRODUCTION: Repetitive peripheral sensory stimulation (RPSS) followed by 4-hour task-specific training (TST) improves upper limb motor function in subjects with stroke who experience moderate to severe motor upper limb impairments. Here, we compared effects of RPSS vs sham followed by a shorter duration of training in subjects with moderate to severe motor impairments in the chronic phase after stroke. METHODS: This single-center, randomized, placebo-controlled, parallel-group clinical trial compared effects of 18 sessions of either 1.5 h of active RPSS or sham followed by a supervised session that included 45 min of TST of the paretic upper limb. In both groups, subjects were instructed to perform functional tasks at home, without supervision. The primary outcome measure was the Wolf Motor Function Test (WMFT) after 6 weeks of treatment. Grasp and pinch strength were secondary outcomes. RESULTS: In intention-to-treat analysis, WMFT improved significantly in both active and sham groups at 3 and 6 weeks of treatment. Grasp strength improved significantly in the active, but not in the sham group, at 3 and 6 weeks. Pinch strength improved significantly in both groups at 3 weeks, and only in the active group at 6 weeks. CONCLUSIONS: The between-group difference in changes in WMFT was not statistically significant. Despite the short duration of supervised treatment, WMFT improved significantly in subjects treated with RPSS or sham. These findings are relevant to settings that impose constraints in duration of direct contact between therapists and patients. In addition, RPSS led to significant gains in hand strength.Trial Registry Name: Peripheral Nerve Stimulation and Motor Training in Stroke Clinical Trials.gov identifier: NCT0265878 https://clinicaltrials.gov/ct2/show/NCT02658578.

Accuracy of Microcomputed Tomography in Detecting Dentinal Cracks: A Correlative Study with Scanning Electron and Operative Microscopy.

The aim of the study was to evaluate the accuracy of microcomputed tomography (mCT) to detect dentinal cracks when compared with scanning electron microscopy (SEM) and operating microscopy (OM). Different conditions of pixel size (10 or 17 µm), sample moisture (dry/moist), and transillumination (with/without) were evaluated. Additionally, the influence of the dentinal defect width on its detection was analyzed. The root canals of human mandibular incisors were prepared with the Reciproc R40 instrument (VDW, Munich, Germany). The roots were sectioned 5 and 10 mm from the apex, and mCT scans of middle and apical segments were performed at two pixel sizes: 10 µm and 17 µm, under dry and moist conditions (groups: 10dry, 10moist, 17dry, and 17moist). The operating microscope was used with and without transillumination (groups: OMTrans and OM). Findings showed that accuracy was moderate for the 10dry, 10moist, and OMTrans groups, poor for OM and very poor for 17dry and 17moist. The thickness of the dentin crack significantly influenced its detection by mCT using the resolution of 10 µm in both dry and wet conditions (P = .002), 17 µm in the dry condition (P = .002), and by the operating microscope using transillumination (P = .009). Some cracks visualized in SEM were not detected by mCT and an operating microscope. Not only the mCT resolution but also the sample moisture condition and the dentinal crack width can significantly influence its detection.

Human amniotic membrane for the treatment of large and refractory macular holes: a retrospective, multicentric, interventional study.

BACKGROUND: The purpose of the current study is to report the anatomical and functional results of off-label human amniotic membrane graft as primary intervention to repair large to giant macular holes and in reoperations when wide internal limiting membrane peeling was unsuccessful. METHODS: Retrospective chart review was carried out in five different centers to identify all cases that had undergone off-label human amniotic membrane graft for the treatment of large or failed macular holes (MH). Data collected included age, gender, other concomitant diagnosis, symptoms duration, lens status, number of previous surgeries, macular hole measurements (minimum and base linear diameters), mean post-operative follow-up (months), and pre- and post-operative best corrected visual acuity (BCVA). Main outcome measures were anatomical MH closure rates and final BCVA (in logMAR). Nonparametric Wilcoxon rank-sum test was used because the data was not normally distributed, a P values < 0.05 were considered statistically significant. RESULTS: Nineteen eyes of 19 patients were identified and included in the study. Mean age was 66.21 ± 14.96 years and predominantly females (84%). All eyes had successfully closed MH with a single intervention with no recurrences during a mean of 9 ± 3.87 months follow-up. The median BCVA in logMAR preoperative was 1.30 ± 0.44 (0.80-2.0), approximately 20/400 on Snellen chart and the median BCVA in logMAR postoperative was 1.0 ± 0.72 (0.4-3.0) approximately 20/200 (p < 0.0001) with median of three lines of visual improvement. CONCLUSION: The use of human amniotic membrane graft seems to be a viable and effective alternative for the treatment of large and persistent macular holes. However, further larger prospective controlled studies are necessary to confirm our preliminary results of this new surgical technique.

Corrosion resistance assessment of nickel-titanium endodontic files with and without heat treatment.

OBJECTIVES: The aim of this study was to evaluate the corrosion resistance of heat-treated (Reciproc and WaveOne) and non-heat-treated (ProTaper and Mtwo) superelastic nickel-titanium endodontic files when immersed in a 5.25% sodium hypochlorite solution. MATERIALS AND METHODS: Anodic polarization curves were obtained with potential sweeps that began at the open circuit potential or corrosion potential (Ecorr). The pitting potential (Epit) was identified on the anodic polarization curve as the potential at which a sudden increase in current was observed. The micromorphology of the 28 tested files was analyzed before and after the electrochemical assay using scanning electron microscope (SEM). The data were analyzed using 1-way analysis of variance with the post hoc Bonferroni test (for Ecorr) and the Student t-test for independent samples (for Epit). RESULTS: The mean Ecorr values were 0.506 V for ProTaper, 0.348 V for Mtwo, 0.542 V for Reciproc, and 0.321 V for WaveOne files. Only WaveOne and Protaper files exhibited pitting corrosion, with Epit values of 0.879 V and 0.904 V, respectively. On the SEM images of the ProTaper and WaveOne files, cavities suggestive of pitting corrosion were detected. CONCLUSIONS: Signs of corrosion were observed in both heat-treated and non-heat-treated files. Of the evaluated files, WaveOne (a heat-treated file) and ProTaper (a non-heat-treated file) exhibited the lowest corrosion resistance.

Supplementing filling material removal with XP-Endo Finisher R or R1-Clearsonic ultrasonic insert during retreatment of oval canals from contralateral teeth.

This study compared the efficacy of XP-Endo Finisher R and R1-Clearsonic insert in removing filling material remnants from oval canals. Twelve pairs of contralateral premolars were treated and subsequently retreated with Reciproc 50. A supplementary procedure with XP-Endo Finisher R or R1-Clearsonic was performed. Micro-computed tomography was used to quantify the filling material volume in the full canal and apical segment lengths. Intragroup analyses revealed significant reduction of filling material after both procedures, not only in the full canal but also in the apical segment (P < 0.05). The amount of filling material removed with XP-Endo Finisher R and R1-Clearsonic was 47.9% and 52.2% in the apical segment (P > 0.05), and 82.1% and 64.6% in the full canal (P < 0.05). None of the instruments was effective in completely removing the filling material from the apical canal, but better results were obtained with XP-Endo Finisher R in the total canal length.

Invasive cervical resorption of central incisor during orthodontic treatment

ABSTRACT Introduction: Invasive cervical resorption (ICR) is a relatively rare type of ERR (External Root Resorption), in which a localized resorption begins in the cervical area of the tooth, below the epithelial junction and above the ridge crest. Objective: Describe the clinical case of an 11-year-old boy with no dental trauma history, presenting moderate crowding and ectopic eruption of the maxillary right central incisor. He had been undergoing orthodontic treatment elsewhere, and his family was dissatisfied with the results. Description: A new treatment was indicated, which included rapid maxillary expansion followed by extraction of four premolars. During routine panoramic evaluation, a radiolucid image was detected and a periapical radiograph was requested. At this point, an ICR of the maxillary right central incisor was found. The treatment was cautiously finalized and despite the use of light forces, central incisor was severally compromised by ICR and was therefore extracted. Conclusion: This clinical example discusses the importance of routine radiographs for the early diagnoses of ICR.

RESUMO Introdução: A reabsorção cervical invasiva (RCI) é um tipo relativamente raro de reabsorção radicular externa (RRE), no qual uma reabsorção localizada começa na região cervical do dente, abaixo da junção epitelial e acima da crista marginal. Objetivo: Descrever o caso clínico de um menino com 11 anos de idade, sem histórico de trauma dentário, apresentando apinhamento moderado e erupção ectópica do incisivo central superior. Ele realizava tratamento ortodôntico em outro local, mas sua família estava insatisfeita com os resultados. Descrição: Foi iniciado um novo tratamento, que incluiu a expansão rápida da maxila, seguida pela extração de quatro pré-molares. Durante a avaliação de rotina da radiografia panorâmica, uma imagem radiolúcida foi detectada, e uma radiografia periapical da região foi solicitada, sendo encontrada uma RCI no incisivo central superior direito. O tratamento foi finalizado com cautela e, apesar do uso de forças leves, o incisivo central estava seriamente comprometido pela RCI e, portanto, precisou ser extraído. Conclusão: Esse exemplo clínico discute a importância das radiografias de rotina para o diagnóstico precoce da RCI.