Exploring access cavity through non-carious cervical lesions: Impacts on instrumentation, obturation, and fracture resistance in mandibular incisors.

AIM: To compare the effects of Cervical Access Cavity (CervAC) and Traditional Access Cavity (TradAC) on root canal preparation, root canal filling, and fracture resistance in mandibular incisors. METHODOLOGY: Twenty recently extracted and intact mandibular incisors were initially scanned using a micro-CT device. The specimens were anatomically matched to create two groups (n = 10). A wedge-shaped non-carious cervical lesion (NCCL) was created on the buccal aspect of all teeth using a double-faced segmented diamond disc. In group 1, a TradAC was prepared, whilst in group 2, access was created through the simulated NCCL using a round diamond bur 1012. After root canal preparation with Rotate instruments sizes 15/0.04, 20/0.04, and 25/0.04, the teeth were scanned again and evaluated for root canal volume and surface area, static voxels, volume of removed dental tissue, and dentine thickness. After that, the root canals were filled using the single-cone technique, teeth were restored with composite resin, and subsequently rescanned to calculate the volume of filling materials and voids. Then, the restored teeth were subjected to fracture resistance tests using a universal testing machine. Statistical comparisons between groups were performed with the Mann-Whitney test or the Student's t-test, with a statistical significance level of 5%. RESULTS: Statistical comparisons indicated no significant differences between groups in terms of root canal volume, surface area, static voxels, removed root dentine, root canal filling volume, percentage of voids, or fracture resistance load (p > .05). Conversely, teeth prepared with TradAC showed a significantly higher percentage of dental tissue removed from the crown (p = .001) and a greater volume of filling material remnants in the pulp chamber (p < .001) compared to the CervAC group. A significantly lower percentage reduction in dentine thickness was observed only on the mesial aspect of root at Level 1 in TradAC group (p = .008). CONCLUSIONS: CervAC can be considered a viable alternative approach in the presence of NCCL in mandibular incisors.

Innovations produced in Primary Health Care during the COVID-19 pandemic: an integrative literature review. / Inovações produzidas na Atenção Primária à Saúde durante a pandemia do COVID-19: uma revisão integrativa da literatura.

Primary Health Care (PHC) proved to be an important part of the prevention, control and treatment measures against COVID-19, a situation in which it was challenged to keep up its provision of regular services as well. This article identifies the main arrangements made to provide PHC care in the context of the COVID-19 pandemic. An integrative literature review of articles found in PubMed, SciELO and LILACS databases was performed using the descriptors "Primary Health Care" and "COVID-19". Findings were analyzed considering three questions: Information and Communication Technologies (ICT), Organizations of Work Processes and Non-COVID Chronic Diseases. The use of different forms of ICT to provide PHC is highlighted regarding patients with respiratory symptoms and chronic patients. Changes in team composition, service flows, physical spaces and working hours were also introduced. Although strategies aimed at monitoring chronic patients and at remote care may have helped minimize deterioration of their health, the decrease in the number of visits performed during this period could have resulted in an increased demand for PHC in post-pandemic years.

A Atenção Primária à Saúde (APS) demonstrou ser parte importante das medidas de prevenção, controle e tratamento do COVID-19, ao mesmo tempo em que foi desafiada a manter a oferta dos serviços regulares. O objetivo deste artigo é identificar os principais arranjos desenvolvidos para ofertar cuidados na APS na pandemia do COVID-19. A revisão integrativa foi realizada nas bases de dados PubMed, SciELO e LILACS por meio dos descritores "Atenção Primária à Saúde" e "COVID-19". Os resultados foram analisados por meio de três questões: Tecnologias de Informação e Comunicação (TIC), Organizações dos Processos de Trabalho e Doenças Crônicas Não-COVID. Ganha grande destaque o uso das TIC no cuidado ofertado na APS, tanto para pacientes com sintomas respiratórios quanto para pacientes crônicos. Alterações na composição das equipes, fluxos de atendimento, espaços físicos e horários de atendimento também foram implantadas. Ainda que estratégias que visaram o monitoramento dos pacientes crônicos e o atendimento remoto podem ter contribuído para minimizar os agravos à saúde desses usuários, a diminuição dos atendimentos realizados neste período poderá resultar em uma grande demanda para a APS nos anos pós-pandemia.

Inovações produzidas na Atenção Primária à Saúde durante a pandemia do COVID-19: uma revisão integrativa da literatura / Innovations produced in Primary Health Care during the COVID-19 pandemic: an integrative literature review

Resumo A Atenção Primária à Saúde (APS) demonstrou ser parte importante das medidas de prevenção, controle e tratamento do COVID-19, ao mesmo tempo em que foi desafiada a manter a oferta dos serviços regulares. O objetivo deste artigo é identificar os principais arranjos desenvolvidos para ofertar cuidados na APS na pandemia do COVID-19. A revisão integrativa foi realizada nas bases de dados PubMed, SciELO e LILACS por meio dos descritores "Atenção Primária à Saúde" e "COVID-19". Os resultados foram analisados por meio de três questões: Tecnologias de Informação e Comunicação (TIC), Organizações dos Processos de Trabalho e Doenças Crônicas Não-COVID. Ganha grande destaque o uso das TIC no cuidado ofertado na APS, tanto para pacientes com sintomas respiratórios quanto para pacientes crônicos. Alterações na composição das equipes, fluxos de atendimento, espaços físicos e horários de atendimento também foram implantadas. Ainda que estratégias que visaram o monitoramento dos pacientes crônicos e o atendimento remoto podem ter contribuído para minimizar os agravos à saúde desses usuários, a diminuição dos atendimentos realizados neste período poderá resultar em uma grande demanda para a APS nos anos pós-pandemia.

Abstract Primary Health Care (PHC) proved to be an important part of the prevention, control and treatment measures against COVID-19, a situation in which it was challenged to keep up its provision of regular services as well. This article identifies the main arrangements made to provide PHC care in the context of the COVID-19 pandemic. An integrative literature review of articles found in PubMed, SciELO and LILACS databases was performed using the descriptors "Primary Health Care" and "COVID-19". Findings were analyzed considering three questions: Information and Communication Technologies (ICT), Organizations of Work Processes and Non-COVID Chronic Diseases. The use of different forms of ICT to provide PHC is highlighted regarding patients with respiratory symptoms and chronic patients. Changes in team composition, service flows, physical spaces and working hours were also introduced. Although strategies aimed at monitoring chronic patients and at remote care may have helped minimize deterioration of their health, the decrease in the number of visits performed during this period could have resulted in an increased demand for PHC in post-pandemic years.

Effects of increasing instrument size and taper on the disinfection and shaping of mandibular incisors.

This study assessed canal preparation effects on disinfection and dentin preservation. Thirty mandibular incisors were paired into two experimental groups (n = 10). Following contamination, the initial microbial sample was collected. Instruments 30/0.03 (Group 1) and 30/0.05 (Group 2) were employed and a second sample was obtained. Canals were enlarged using instruments 40/0.03 and 40/0.05, respectively, and a third sample was collected. Final irrigation was performed, and sample S4 obtained. A final scan evaluated volume, surface area, unprepared areas, removed dentin and dentin thickness. Data were analysed using Student t-test, Mann-Whitney, Kruskal-Wallis and Dunn tests. A significant difference was observed between S1 and other time points (p < 0.05). Comparison between groups showed no differences in bacterial loads and in the percentage of microbial reduction (p > 0.05). Group 2 exhibited greater reduction in dentin thickness than group 1 in the mesial aspect of the root (p < 0.05). Instrument 30/0.03 might provide effective disinfection and safety during mandibular incisors canal preparation.

Are CAD-CAM milled glass fiber posts better than prefabricated or custom glass fiber posts for endodontically treated teeth? A systematic review with meta-analysis.

STATEMENT OF PROBLEM: Prefabricated and custom glass fiber posts have been successfully used to reconstruct endodontically treated teeth. However, the performance of computer-aided design and computer-aided manufacture (CAD-CAM) milled glass fiber posts is unclear. PURPOSE: The purpose of this systematic review with meta-analysis was to compare the fracture and bond strength and cement layer thickness of CAD-CAM milled glass fiber posts with prefabricated or custom glass fiber posts. MATERIAL AND METHODS: The protocol was registered in the Open Science Framework (http://osf.io/65jm7). Two reviewers searched the PubMed/MEDLINE, Web of Science, Embase, Scopus, and ProQuest databases for articles up to September 2023. In addition, the reference lists were hand searched. A meta-analysis was performed by using the RevMan 5.4 program. The risk of bias was assessed using the RoBDEMAT tool. RESULTS: After screening, a total of 18 studies were included. The CAD-CAM milled glass fiber posts showed higher fracture strength (P=.02; Standardized Mean Difference [SMD]: 0.57; 95% Confidence Interval [CI]: 0.07 to 1.07), bond strength (P=.010; SMD: 1.07; 95% CI: 0.26 to 1.89), and lower cement layer thickness (P=.009; SMD: -2.94; 95% CI: -5.15 to -0.73) when compared with prefabricated glass fiber posts. However, fracture strength (P=.53; SMD: 0.38; 95% CI: -0.79 to 1.54) and bond strength (P=.90; SMD: -0.05; 95% CI: -0.81 to 0.72) were statistically similar between CAD-CAM milled and custom glass fiber posts. Significant and substantial heterogeneity was observed in all meta-analyzes (P<.01; I>60%). The studies sufficiently reported most domains related to bias, except for randomization of samples, sample size rationale and reporting and operator blinding. CONCLUSIONS: CAD-CAM milled and custom glass fiber posts provide an effective and safe option for restoring endodontically treated teeth, especially for weakened teeth or enlarged root canals. However, further well-designed clinical research is recommended to strengthen these findings.

What makes an article a must read in medical education?

BACKGROUND: The dissemination of published scholarship is intended to bring new evidence and ideas to a wide audience. However, the increasing number of articles makes it challenging to determine where to focus one's attention. This study describes factors that may influence decisions to read and recommend a medical education article. METHODS: Authors analyzed data collected from March 2021 through September 2022 during a monthly process to identify "Must Read" articles in medical education. An international team of health sciences educators, learners, and researchers voted on titles and abstracts to advance articles to full text review. Full texts were rated using five criteria: relevance, methodology, readability, originality, and whether it addressed a critical issue in medical education. At an end-of-month meeting, 3-4 articles were chosen by consensus as "Must Read" articles. Analyses were used to explore the associations of article characteristics and ratings with Must Read selection. RESULTS: Over a period of 19 months, 7487 articles from 856 journals were screened, 207 (2.8%) full texts were evaluated, and 62 (0.8%) were chosen as Must Reads. During screening, 3976 articles (53.1%) received no votes. BMC Medical Education had the largest number of articles at screening (n = 1181, 15.8%). Academic Medicine had the largest number as Must Reads (n = 22, 35.5%). In logistic regressions adjusting for the effect of individual reviewers, all rating criteria were independently associated with selection as a Must Read (p < 0.05), with methodology (OR 1.44 (95%CI = 1.23-1.69) and relevance (OR 1.43 (95%CI = 1.20-1.70)) having the highest odds ratios. CONCLUSIONS: Over half of the published medical education articles did not appeal to a diverse group of potential readers; this represents a missed opportunity to make an impact and potentially wasted effort. Our findings suggest opportunities to enhance value in the production and dissemination of medical education scholarship.

Root canal dentin wear during final irrigation in endodontic retreatment with passive ultrasonic irrigation and easy clean instruments.

Context: Complementary procedures have been proposed to improve the endodontic retreatments. Aim: The aim of this study was to evaluate, by microcomputed tomography (micro-CT), the dentin wear caused by passive ultrasonic irrigation (PUI) and easy clean (EC) instruments, when used for the final removal of filling material during endodontic retreatment. Methods: Thirty-six mesial roots of the lower first molars were divided into four groups (n = 9), according to the final irrigation and sealer: PUI/AH Plus, EC/AH Plus, PUI/Total Fill (TF), and EC/TF. Canal volume was evaluated, both before and after the final irrigation, by micro-CT analysis. The Kruskal-Wallis test was used to compare the volumes among groups and the paired Wilcoxon test was used to compare the volume values before and after the final irrigation within each group. Results: Both complementary cleaning procedures promoted dentin wear that was observed only when the volume was analyzed for each third of the root canal. In the apical third, both instruments showed significant wear, where the use of the EC instrument resulted in greater wear than the PUI, in teeth filled with both AH Plus and TF BC Sealers (P < 0.05). Conclusion: Both complementary cleaning procedures promoted dentin wear and must be used cautiously.

Efficacy of the treatment using a microemulsion loaded with epoxy-α-lapachone in combination with meglumine antimoniate against murine infection by Leishmania (Leishmania) amazonensis.

Leishmaniasis is a disease caused by Leishmania spp., affecting millions of people around the world. For decades, its treatment has been based on pentavalent antimonials, which notoriously cause toxic side effects in patients. In this study, epoxy-α-lapachone incorporated into an oil-in-water-type microemulsion (ELAP-ME) and meglumine antimoniate (MA) were assayed in monotherapy and in combination (ELAP-ME/MA) in BALB/c mice infected with Leishmania (Leishmania) amazonensis. In general, there was a reduction in paw lesion size (up to 37% reduction) and decreases of parasite loads in the footpad (∼40%) and lymph nodes (∼31%) of animals treated with ELAP-ME/MA, when compared to the non-treated control groups. Analyses of serum biochemical parameters revealed that the ELAP-ME/MA showed lower renal and hepatic toxicity when compared to MA 2-doses/week monotherapy. These findings indicate that the ELAP-ME/MA combination may be a promising approach for the treatment of cutaneous leishmaniasis.

Can the addition of surfactants to NaOCl irrigation impact on the percentage of voids of root canal filling?

This study evaluated the impact of canal irrigation using surfactants associated to NaOCl on the percentage of voids of root canal filling through micro-computed tomographic (micro-CT) analysis. 27 mandibular mesial roots with Vertucci type II canal configuration with isthmus were selected and scanned in a micro-CT device. The specimens were assigned to three groups (n = 9), according to the irrigation solution during instrumentation: 2.5% NaOCl without additives (control), 2.5% NaOCl with 0.1% Benzalkonium Chloride and 2.5% NaOCl with 0.1% Tween 80. After obturation, the specimens were rescanned, and the percentage of voids were calculated. Data were analysed using one-way ANOVA with a significance level of 5%. The percentage of voids were similar among the groups (p > 0.05). None of the specimens showed completely voids-free areas. The addition of surfactants to NaOCl irrigation did not improve the quality of root canal filling of mandibular mesial root canals.

Impact of Calcium-Hydroxide, Sodium Ascorbate, and Sodium Thiosulphate on Bond Strength of Composite Restorations to Bleached Dentin.

This study evaluated the impact of using calcium-hydroxide or the antioxidant agents on the bond strength of adhesive restorations to bleached dentin. Forty teeth were prepared and allocated into 8 groups according to the surface treatment after bleaching (application or not of calcium hydroxide, 10% sodium ascorbate and 5% sodium thiosulphate for 10min), and the time of final restoration (immediate or after 7-days). Sodium perborate with 20% hydrogen peroxide was applied for 3 weeks using a developed artificial pulp chamber, with replacement every week. Composite resin restoration was performed and microtensile test was performed. Then, specimens were analyzed using a stereomicroscope and SEM. Data was submitted to Kruskal-Wallis and Dunn tests (p<0.05). The bond strength of non-bleached teeth was similar to the groups restored after 7 days of bleaching (p<0.05). The lowest values of bond strength were showed by groups restored immediately after bleaching (p<0.05). In all groups, there was a considerable predominance of adhesive fractures. Delaying the final restoration of teeth submitted to nonvital bleaching for 7 days permits an increase in bond strength. The immediate restoration of bleached teeth after the use of 10% sodium ascorbate or 5% sodium thiosulfate for 10 minutes showed unsatisfactory results. Clinical relevance Irrespective of the dentin protocol applied before adhesion, a satisfactory and an unsatisfactory result of bond strength values will be obtained delaying the final restoration or immediately performing the final restoration, respectively. Therefore, after nonvital tooth bleaching, clinicians should always delay the final restoration for a minimum period of 7 days.

Chronic alcohol and nicotine consumption as catalyst for systemic inflammatory storm and bone destruction in apical periodontitis.

AIM: To assess the periapical alveolar bone pattern and the serum levels of proinflammatory cytokines, biochemical markers and metabolites in rats subjected to chronic alcohol and nicotine consumption and induced apical periodontitis. METHODOLOGY: Twenty-eight male Wistar rats were divided into four groups: Control, Alcohol, Nicotine and Alcohol+Nicotine. The alcohol groups were exposed to self-administration of a 25% alcohol solution, while the other groups were given only filtered water. The nicotine groups received daily intraperitoneal injections of a nicotine solution (0.19 µL of nicotine/mL), whereas the other groups received saline solution. Periapical lesions were induced by exposing the pulps of the left mandibular first molars for 28 days. After euthanasia, the mandibles were removed and the percentage bone volume, bone mineral density, trabecular thickness, trabecular separation and trabecular number of the periapical bone were measured using micro-computed tomography images. Serum samples were collected for analysis of proinflammatory cytokines (IL-1ß, IL-4, IL-6 and TNF-α), biochemical and metabolomic analysis. Statistical analysis was performed with a significance level of 5%. Nonparametric data were analysed using the Kruskal-Wallis test followed by Dunn's test, while one-way anova followed by Tukey's test was performed for parametric data. RESULTS: The groups exposed to alcohol or nicotine consumption exhibited an altered bone pattern indicating lower bone density and higher levels of IL-1ß, IL-6 and TNF-α compared to the Control group (p < .05). Significant differences were observed among the groups in the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, cholesterol, triglycerides, urea, creatinine, albumin, uric acid, bilirubin and calcium. Metabolomic analysis revealed significant differences in glycine, phosphocholine, lysine, lactate, valine, pyruvate and lipids (CH2 CH2 CO), n(CH2 ) and n(CH3 ). Most of these parameters were even more altered in the simultaneous consumption of both substances compared to single consumption. CONCLUSION: Alcohol and nicotine chronic consumption altered several metabolic markers, impaired liver and kidney function, increased the production of systemic proinflammatory mediators and harmed the periapical bone microarchitecture in the presence of apical periodontitis. The simultaneous consumption of alcohol and nicotine intensified these detrimental effects.

Intraradicular Dentinal Changes Following Fiber Postremoval: Micro-computed Tomography Analysis.

Context: Excessive dentine wear during postremoval can occur due to the adhesion between the cement and the post. Aim: The aim is to evaluate dentine wear and microcrack occurrence following the removal of intraradicular fiberglass posts that were previously cemented with two types of resin cement. Methods: Distal roots (n = 38) of lower molars were instrumented, filled, prepared for intraradicular postinstallation, and divided into two groups according to the cement used for the posts: RelyX ARC or RelyX U200. The posts were removed through abrasion using ultrasonic diamond tips, after which the degrees of dentine wear (volume/mm3) and microcrack formation were assessed using microcomputed tomographic imaging. Statistical Analysis Used: The Mann-Whitney U (P ≤ 0.05) and Chi-squared tests (P ≤ 0.05) were used. Results: After the removal of the posts, no statistically significant difference in root canal volume or microcrack occurrence was observed between the groups (P > 0.05). The procedure produced significant dentine wear regardless of the type of cement used (P < 0.05). Conclusions: The removal of fiberglass posts caused extensive dentine wear but did not influence microcrack occurrence. The type of resin cement used did not affect the dentine loss or microcrack appearance that resulted from fiberglass postremoval.

Analysis of Different Tidal Volumes on Ventilatory Mechanics and Arterial Blood Gas Variables in Patients Undergoing Cardiac Surgery.

Introduction: Cardiovascular diseases have been increasing gradually each year, and their incidence has reached 80%. Mechanical ventilation (MV) is essential in the postoperative period of cardiac surgery (CS) due to anesthetic induction. The tidal volume (TV) is a parameter that depends on the conditions of the respiratory system mechanics, aiming at the reduction of dynamic hyperinflation. Objective: Analyze the effect of different TVs on blood gas analysis variables and respiratory mechanics in patients submitted to CS. Materials and methods: This was an uncontrolled randomized clinical trial. Patients were randomized by lottery into the following two groups: One group was ventilated with a TV of 6 mL/kg; while the other received a TV of 8 mL/kg. After 30 minutes of admission with the VT, blood gas analysis data were evaluated, such as pH, oxygen arterial pressure (PaO2), arterial pressure of carbon dioxide (PaCO2), and peripheral oxygen saturation (SpO2). The evaluation of respiratory mechanics was composed of static and dynamic compliance, airway resistance, and driving pressure. Results: A total of 78 patients were included, 58% of whom were males with a mean age of 55 ± 13 years. It was observed that there were no significant differences regarding respiratory mechanics, only the driving pressure presented statistical significance, the group 6 mL/kg was 8.3 ± 2.5 in the group 8 mL/kg 10.4 ± 2.1 presenting a value of (p < 0.001). Conclusion: Based on the findings of the present study, we conclude that different TVs do not significantly alter the blood gas variables and do not influence the respiratory mechanics of patients undergoing CS. How to cite this article: Cordeiro A, Souza A, de Brito Lima CR, Araújo J, Mascarenhas H, Guimarães A. Analysis of Different Tidal Volumes on Ventilatory Mechanics and Arterial Blood Gas Variables in Patients Undergoing Cardiac Surgery. Indian J Crit Care Med 2023;27(12):930-933.

Mask region-based CNNs for cervical cancer progression diagnosis on pap smear examinations.

This research presents a novel approach for cervical cancer detection and segmentation using tissue images with multiple cells. The study employs a novel deep learning architecture based on Mask Region-Based Convolutional Neural Network (RCNN) and statistical analysis. This new architecture enables us to achieve a high percentage of detection and pix-to-pix area segmentation. A mean Average Precision (mAP) higher than 60% for 3-class and 5-class was achieved. In addition, higher F1-scores of 70% for 3-class and 5-class were obtained. This investigation is a collaborative work, where a medical consultant collected the samples from the Papanicolaou (Pap) Smear examination and labeled the cells presented to the liquid-based cytology (LBC). Furthermore, the online available benchmark data set, SIPaKMeD, was also utilized. Additionally, sample images from the Mendeley data set were also labeled by the trained medical consultant for comparison. The proposed scheme automatically generates a full report for a medical consultant to identify the location of the malicious cells in the given images and expedite the diagnosis and treatment process.

Clinical, epidemiological and laboratory characteristics of cases of Covid-19-related maternal near miss and death at referral units in northeastern Brazil: a cohort study.

Objective: Covid-19 poses a major risk during pregnancy and postpartum, resulting in an increase in maternal mortality worldwide, including in Brazil; however, little research has been conducted into cases of a near miss. This study aimed to describe the frequency of COVID-19-related near miss and deaths during pregnancy or in the postpartum in referral centers in northeastern Brazil, as well as the clinical, epidemiological, and laboratory characteristics of the women who experienced a severe maternal outcome.Methods: A retrospective and prospective cohort study was performed between April 2020 and June 2021 with hospitalized pregnant and postpartum women with a diagnosis of COVID-19 confirmed by real-time polymerase chain reaction (RT-PCR). Data from five tertiary hospitals in northeastern Brazil were evaluated. Descriptive statistical analysis was performed using Epi Info, version 7.2.5.0.Results: A total of 463 patients were included. Of these, 64 (14% of the sample) had a severe maternal outcome, with 42 cases of near miss (9%) and 22 maternal deaths (5%). Patients who had a severe maternal outcome were predominantly young (median age 30 years) and 65.6% were black or brown-skinned. The women had between 6 and 16 years of schooling; 45.3% had a stable partner; 81.3% were pregnant at the time of admission to the study; and 76.6% required a Cesarean section. The great majority (82.8%) had severe acute respiratory syndrome (SARS). Other complications included hypertensive syndromes (40.6%), pneumonia (37.5%), urinary tract infections (29.7%), acute renal failure (25.0%) and postpartum hemorrhage (21.9%). Sepsis developed in 18.8% of cases, neurological dysfunction in 15.6%, and hepatic dysfunction and septic shock in 14.1% of cases each. The relative frequency of admission to an intensive care unit was 87.5%, while 67.2% of the patients required assisted mechanical ventilation, and 54.7% required noninvasive ventilation. Antibiotics were prescribed in 93.8% of cases and corticosteroids in 71.9%, while blood transfusion was required in 25.0% of cases and renal replacement therapy in 15.6%. Therapeutic anticoagulants were administered to 12.5% of the patients. Of the patients who had a severe maternal outcome, the frequency of respiratory dysfunction was 93.8%, with 50.0% developing neurological dysfunction and 37.5% cardiovascular dysfunction. Hematological dysfunction was found in 29.7%, renal dysfunction in 18.8%, and uterine dysfunction in 14.1%. Hepatic dysfunction occurred in 7.8% of the sample. The near-miss ratio for Covid-19 was 1.6/1000 live births and the maternal mortality ratio for Covid-19 was 84.8/100,000 live births, with a mortality index of 34.4% in the sample.Conclusion: This study revealed a low Covid-19-related maternal near miss (MNM) ratio of 1.6/1000 live births and a high Covid-19-related maternal mortality ratio (MMR) of 84.81/100,000 live births. The mortality index was also high. Most of the patients were admitted while pregnant, were young, married and black or brown-skinned, and none had completed university education. The majority had SARS and required admission to an intensive care unit and mechanical ventilation. Most were submitted to a Cesarean section.

Effect of the progressive taper enlargement of buccal root canals of three-rooted maxillary molars: A stepwise micro-CT study.

This study evaluated unprepared canal areas, volume of dentine removal, and dentine thickness after the progressive enlargement of the buccal canals of 22 maxillary molars, with and without the MB2, using instruments with the same tip size (0.25 mm) but 4 different tapers (0.03, 0.05, 0.06 and 0.08 v). Micro-CT scans were performed after each instrument. Data were compared using a general linear mixed model post hoc comparisons with Kenward-Roger for Wald F tests (α = 5%). After each treatment step, it was observed an increase in the percentage volume of removed dentine and a decrease in the unprepared areas and dentine thickness at the pericervical region of all canals (p < 0.05). The percentage reduction of dentine thickness in MB2 canal was higher than in the mesiobuccal and distobuccal canals (p < 0.05). Knowledge of pre-operative dimensions and dentine thickness before enlargement of buccal canals of maxillary molars is an important factor to avoid excessive dentine removal.

Volumetric changes in root canal sealers in ex vivo and a novel animal model approach.

AIM: This study aimed to evaluate the volumetric change of root canal sealers through micro-computed tomographic analysis using a novel in vivo model and to compare the results with those obtained using an ex vivo test. METHODOLOGY: Eighteen single-rooted teeth were cut to 5 mm length from the root apex. The root canals were uniformly enlarged and filled with EndoSequence BC Sealer or AH Plus Jet root canal sealers. Samples were stored at 37°C and 95% relative humidity for 24 h and then scanned with a micro-CT device. Twelve samples (n = 6 for each sealer) were implanted in the subcutaneous tissue of Wistar rats, while six samples (n = 3 for each sealer) were immersed in 20 mL of phosphate-buffered saline (PBS) at 37°C at neutral pH. After 7 and 30 days, teeth were removed from subcutaneous tissue or PBS and rescanned. Statistical analysis of volume changes was performed using Shapiro-Wilk's test and independent t-test (p < .05). RESULTS: AH Plus Jet had smaller volume changes (-2.2 to +0.77%) than EndoSequence BC Sealer (-2.0 to +4.0%) (p < .05), in the two tested models. The volume of the root canal sealers decreased over time (p < .05), in vivo. AH Plus Jet results varied between the in vivo and ex vivo results (p < .05), while EndoSequence BC Sealer presented similar volume losses for both experimental models (p > .05). CONCLUSION: EndoSequence BC Sealer lost more volume than AH Plus Jet. The experimental conditions influenced the volumetric change of AH Plus Jet but not the EndoSequence BC Sealer. The ex vivo model should be further explored as a methodological alternative to assess the volumetric changes of root canal sealers without causing harm to animals.

Calcareous sponges can synthesize their skeleton under short-term ocean acidification.

Calcifying organisms are considered as threatened by ocean acidification, because of their calcium carbonate skeleton. This study investigated if a calcareous sponge could synthesize its skeleton (i.e. spicules) under ocean-acidification conditions. Sponge cell aggregates that have the potential to develop into a functional sponge, called primmorphs, were submitted to a 5-day experiment, with two treatments: control (pH 8.1) and acidified conditions (pH 7.6). Primmorphs of the calcareous sponge Paraleucilla magna were able to synthesize a skeleton, even under low pH, and to develop into functional sponges. The spicules had the same shape in both conditions, although the spicules synthesized in low pH were slightly thinner than those in the control. These results suggest that P. magna may be able to survive near-future ocean-acidification conditions.