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1.
J Adhes Dent ; 26(1): 135-145, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38771025

RESUMO

PURPOSE: To measure zirconia-to-zirconia microtensile bond strength (µTBS) using composite cements with and without primer. MATERIALS AND METHODS: Two Initial Zirconia UHT (GC) sticks (1.8x1.8x5.0 mm) were bonded using four cements with and without their respective manufacturer's primer/adhesive (G-CEM ONE [GOne] and G-Multi Primer, GC; Panavia V5 [Pv5]), and Panavia SA Cement Universal [PSAu], and Clearfil Ceramic Plus, Kuraray Noritake; RelyX Universal (RXu) and Scotchbond Universal Plus [SBUp], 3M Oral Care). Specimens were trimmed to an hour-glass shaped specimen whose isthmus is circular in cross-section. After 1-week water storage, the specimens were either tested immediately (1-week µTBS) or first subjected to 50,000 thermocycles (50kTC-aged µTBS). The fracture mode was categorized as either adhesive interfacial failure, cohesive failure in composite cement, or mixed failure, followed by SEM fracture analysis of selected specimens. Data were analyzed using linear mixed-effects statistics (α = 0.05; variables: composite cement, primer/adhesive application, aging). RESULTS: The statistical analysis revealed no significant differences with aging (p = 0.3662). No significant difference in µTBS with/without primer and aging was recorded for GOne and PSAu. A significantly higher µTBS was recorded for Pv5 and RXu when applied with their respective primer/adhesive. Comparing the four composite cements when they were applied in the manner that resulted in their best performance, a significant difference in 50kTC-aged µTBS was found for PSAu compared to Pv5 and RXu. A significant decrease in µTBS upon 50kTC aging was only recorded for RXu in combination with SBUp. CONCLUSION: Adequate bonding to zirconia requires the functional monomer 10-MDP either contained in the composite cement, in which case a separate 10-MDP primer is no longer needed, or in the separately applied primer/adhesive.


Assuntos
Resinas Compostas , Colagem Dentária , Teste de Materiais , Metacrilatos , Cimentos de Resina , Resistência à Tração , Zircônio , Zircônio/química , Cimentos de Resina/química , Resinas Compostas/química , Metacrilatos/química , Cimentos Dentários/química , Cerâmica/química , Análise do Estresse Dentário , Humanos , Fatores de Tempo , Água/química , Temperatura , Porcelana Dentária/química , Propriedades de Superfície , Materiais Dentários/química , Cimentos de Ionômeros de Vidro
2.
Case Rep Dent ; 2024: 5572481, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560367

RESUMO

This case report details the esthetic rehabilitation of a 32-year-old male patient suffering from sleep bruxism, primarily manifesting as a fracture and significant loss of tooth structure in the anterior maxillary central incisors. To address these concerns, the patient underwent a restorative treatment involving the application of semidirect resin composite veneers on the maxillary incisors and direct resin composite restoration on the incisal regions of the maxillary canines. This approach not only restored the functional integrity of the teeth but also significantly enhanced the patient's esthetic appearance.

3.
Dent J (Basel) ; 12(3)2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38534286

RESUMO

BACKGROUND: We compared the repeatability of the shade determination of resin composite restorations and acrylic teeth in light and darker shades at baseline and after an aging process through two digital tooth color-matching methods: using a Trios 3Shape intraoral scanner and using a Vita Easyshade Compact spectrophotometer. MATERIAL AND METHODS: Forty upper central incisor acrylic teeth in the shade A1 (n = 10) and A3 (n = 10) were randomly assigned to be restored with Filtek Bulk Fill in the shade A1 (n = 10) or A3 (n = 10). Subsequently, 20 Class V cavities were prepared in a standardized manner (mesio-distal = 3.0 mm, cervical-occlusal = 2.0 mm, depth = 1.5 mm). Cavities were restored using an universal adhesive system and resin composite in two increments and were light-cured. The shade difference between the resin composite Class V restorations in acrylic teeth of the A1 and A3 shades was evaluated at baseline and after aging. Aging was simulated using ultraviolet light for 120 h. An Easyshade device and an intraoral scanner were used under D65 illumination. Measurements were taken five times, on top of the restoration and on the acrylic teeth, in a randomized manner. RESULTS: Data analysis was on the calculation of the arithmetic mean for the percentage of repeatability conducted by the Trios scanner and the Easyshade device. There was no statistically significant comparison between the shade measurement devices (p > 0.05). At baseline, the repeatability for both the Trios intraoral scanner and the Vita Easyshade Compact device for artificial teeth in the shades A1 and A3 was 100%. After aging, the trueness recorded by the intraoral scanner and the Easyshade device for artificial teeth in the shade A1 was 80%. For Class V restoration with shade A1, the intraoral scanner recorded 80% trueness and the Easyshade device recorded 60% trueness at baseline. For shade A3, the intraoral scanner recorded 60% trueness and the Easyshade device recorded 60% trueness. CONCLUSIONS: The intraoral scanner and Easyshade device are reliable for baseline shade selection, but their accuracy decreases after aging, particularly for darker shades.

4.
Mayo Clin Proc ; 99(3): 437-444, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38432749

RESUMO

National or statewide estimates of excess deaths have limited value to understanding the impact of the COVID-19 pandemic regionally. We assessed excess deaths in a 9-county geographically defined population that had low rates of COVID-19 and widescale availability of testing early in the pandemic, well-annotated clinical data, and coverage by 2 medical examiner's offices. We compared mortality rates (MRs) per 100,000 person-years in 2020 and 2021 with those in the 2019 reference period and MR ratios (MRRs). In 2020 and 2021, 177 and 219 deaths, respectively, were attributed to COVID-19 (MR = 52 and 66 per 100,000 person-years, respectively). COVID-19 MRs were highest in males, older persons, those living in rural areas, and those with 7 or more chronic conditions. Compared with 2019, we observed a 10% excess death rate in 2020 (MRR = 1.10 [95% CI, 1.04 to 1.15]), with excess deaths in females, older adults, and those with 7 or more chronic conditions. In contrast, we did not observe excess deaths overall in 2021 compared with 2019 (MRR = 1.04 [95% CI, 0.99 to 1.10]). However, those aged 18 to 39 years (MRR = 1.36 [95% CI, 1.03 to 1.80) and those with 0 or 1 chronic condition (MRR = 1.28 [95% CI, 1.05 to 1.56]) or 7 or more chronic conditions (MRR = 1.09 [95% CI, 1.03 to 1.15]) had increased mortality compared with 2019. This work highlights the value of leveraging regional populations that experienced a similar pandemic wave timeline, mitigation strategies, testing availability, and data quality.


Assuntos
COVID-19 , Feminino , Masculino , Humanos , Idoso , Idoso de 80 Anos ou mais , Pandemias , Confiabilidade dos Dados , Doença Crônica
5.
Transpl Infect Dis ; 26(2): e14243, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38407514

RESUMO

This is a case of a kidney transplant recipient who presented with skin lesions, low-grade fevers, and pancytopenia 2 months after his transplant.


Assuntos
Transplante de Rim , Humanos , Argentina , Transplante de Rim/efeitos adversos , América Latina
6.
Reprod Toxicol ; 123: 108518, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38042437

RESUMO

Caffeine intake during pregnancy is common. Caffeine crosses the placenta, raising concerns about its possible deleterious effects on the developing embryo/fetus. Studies on this subject show conflicting results, and still there is no consensus on the recommended dose of caffeine during pregnancy. We performed an integrative review with studies from six databases, using broad MESH terms to allow the identification of publications that addressed the outcomes of caffeine use during pregnancy, with no date limit for publications, in English and Portuguese language. The research returned 16,192 articles. After removing duplicates, screening by title, abstract and full-text, we evaluated 257 and included 59 articles. We found association between caffeine intake and pregnancy loss, low birth weight, cardiac and genital anomalies, higher body mass, and neurodevelopmental and neurobehavioral outcomes. The effects were often dose dependent. No association with prematurity has been demonstrated, but one study showed a small reduction in gestational age with increasing doses of caffeine intake. Defining a safe dose for caffeine intake during pregnancy is a challenging task due to the heterogeneity in study designs and results, as well as the difficulty of reliably assessing the amount of caffeine consumed. In some studies, exposures below the recommended level of caffeine intake during pregnancy (200 mg/day), as suggested by the guidelines, were associated with pregnancy loss, low birth weight, cardiac and genital anomalies, higher body mass, and neurodevelopmental and neurobehavioral outcomes. Well-designed studies with reliable quantification of caffeine intake are needed to assess the safety of low doses during pregnancy.


Assuntos
Aborto Espontâneo , Cafeína , Gravidez , Recém-Nascido , Feminino , Humanos , Cafeína/efeitos adversos , Café/efeitos adversos , Recém-Nascido de Baixo Peso , Idade Gestacional
7.
Reprod Toxicol ; 124: 108527, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38160782

RESUMO

Naproxen reduces the production of prostaglandins via inhibition of the cyclooxygenase. Studies have shown that its administration in women can be related to failed ovulation. Therefore, preclinical investigations must be performed in order to investigate its effects in experimental models. Thus, the aim of this study was to evaluate the effects of naproxen on murine folliculogenesis, ovulation, and female fertility. Female C57BL/6 mice (n = 128 - 6 weeks old) were divided into Control, low (10 mg/kg), and high naproxen (50 mg/kg) groups, who were treated for 8 days and directed to morphofunctional analyses. Follicular quantification showed a reduced percentage of antral follicles in naproxen-treated animals. These treated animals also showed smaller oocytes included in secondary and antral follicles, and the diameter of secondary and antral follicles was also reduced. A reduction in the percentage of Ki67-positive granulosa cells was observed in treated animals that also showed down-regulation of Igf1r compared to control. After an ovarian stimulation protocol, naproxen-treated animals showed a reduction in the percentage of secondary and antral follicles, a reduced number of ovulated oocytes and, corpora lutea, and an increased number of failed ovulations. Finally, naproxen-treated animals also showed a reduction in mating index and pregnancy rate. Our findings suggested that, in mice, naproxen administration (eight days treatment) negatively affects molecular and morphological aspects related to late folliculogenesis, ovulation, and fertility.


Assuntos
Naproxeno , Ovulação , Humanos , Feminino , Camundongos , Animais , Naproxeno/toxicidade , Camundongos Endogâmicos C57BL , Oócitos , Proliferação de Células
8.
Plants (Basel) ; 12(23)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38068658

RESUMO

A water deficit can negatively impact fruit yield and quality, affecting critical physiological processes. Strategies to mitigate water deficits are crucial to global food security. Iodine (I) may increase the efficiency of the antioxidant system of plants, but its role against water deficits is poorly understood. This study aimed to evaluate the effectiveness of I in attenuating water deficits and improving fruit quality, investigating whether metabolic responses are derived from a "priming effect" or stress relief during water deficits. Tomato plants were exposed to different concentrations of potassium iodide (KI) via a nutrient solution and subjected to a water deficit. A water deficit in tomatoes without KI reduced their yield by 98%. However, a concentration of 100 µM of KI increased the yield under a water deficit by 28%. This condition is correlated with increased antioxidant activity, photosynthetic efficiency improvement, and malondialdehyde reduction. In addition, the concentration of 100 µM of KI promoted better fruit quality through antioxidant capacity and a decline in the maturation index. Therefore, KI can be an alternative for attenuating water deficits in tomatoes, inducing positive responses during the water deficit period while at the same time improving fruit quality.

9.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1528847

RESUMO

This study aimed to compare the subgingival microbiota of subjects with and without breast cancer (BC). Patients with BC (Group 1; n= 50) and without BC (Group 2; n=50) with periodontitis (A) and without periodontitis (B). The study was conducted in two phases (P1 and P2). One biofilm sample was collected from each subject and analyzed by DNA-DNA Hybridization (Checkerboard DNA-DNA). The relative abundance of the subgingival microbiota differed between the Case and Control groups. However, some species were higher in patients in the Case than in Control subjects and differed between the groups in both phases. Composition of the subgingival microbial community according to the Socransky complex was related to periodontal disease, followed by clinical attachment of level (CAL ≥4mm), age, and tooth loss, which were found to be abundant in Cases when compared with controls. Patients with Tumor Grade II and III had a higher prevalence of tooth loss and CAL≥4mm. It was concluded that in individuals with BC, the sub-gingival microbiota exhibited atypical changes, but they developed periodontal disease.


El objetivo de este estudio fue comparar la microbiota subgingival de sujetos con y sin cáncer de mama (CM). Pacientes con CM (Grupo 1; n= 50) y sin CM (Grupo 2; n=50) con periodontitis (A) y sin periodontitis (B). El estudio se realizó en das fases (P1 y P2). Se recogió una muestra de biopelícula de cada sujeto y se analizó mediante hibridación ADN-ADN (tablero de ajedrez ADN-ADN). La abundancia relativa de la microbiota subgingival difirió entre los grupos de Caso y Control. Sin embargo, algunas especies fueron más altas en los pacientes del Caso que en los sujetos del Control y difirieron entre los grupos en ambas fases. La composición de la comunidad microbiana subgingival según el complejo de Socransky se relacionó con la enfermedad periodontal, seguida por el nivel de inserción clínica (CAL≥4mm), la edad y la pérdida de dientes, que se mostró abundante en los casos en comparación con los controles. Los pacientes con Tumor Grado II y III tuvieron mayor prevalencia de pérdida dental y CAL≥4mm. Se concluyó que en individuos con CM la microbiota subgingival presentó cambios atípicos, pero sin embargo, desarrollaron enfermedad periodontal.

10.
Int J Dent ; 2023: 3327275, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37942468

RESUMO

Introduction: The aim of this study was to evaluate the effect of heating of bioceramic and epoxy resin-based sealers on their micro-push-out bond strength (BS) to root canal dentin. Methods: After criterial selection, 30 human teeth were decoronated and 1-mm thick slices (n = 60) were obtained perpendicularly along tooth axis, from cervical and middle root thirds, with a diamond disc attached to a cutting machine. In each slice, three 1.0-mm diameter orifices were made. After rinsing with 17% EDTA and 2.5% NaOCl, each orifice was filled with Bio-C Sealer or BioRoot RCS or AH Plus, according to the manufacturers' instructions. After filling, half of the slices (n = 30) were heated at 100°C for 1 min, and the other half were kept at room temperature. After 7 days-controlled storage, micro-push-out test was performed in a Universal Testing Machine. Failures were analyzed using a stereomicroscope. Statistical analysis was performed with One-Way ANOVA and post hoc Tukey (α = 5%) tests. Results: AH Plus demonstrated higher BS values after heating (p=0.001) when compared to nonheated. The other sealers did not show a statistically significant difference (p > 0.05). When heated, the average BS values for AH Plus were higher than for BioRoot RCS and Bio-C Sealer (p < 0.001). Cohesive failure mode was the most frequent, followed by adhesive and mixed ones. Conclusion: Heating provided a higher push-out BS to root dentin for AH Plus and did not influence BioRoot RCS or Bio-C sealer.

11.
Gen Dent ; 71(6): 56-60, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37889245

RESUMO

The use of dental ceramics on anterior teeth is associated with predictable and long-lasting esthetic results. However, treatment on darkened substrates is challenging. Various conservative options, including ceramic veneers, are available to change the shape and color of anterior teeth. The aim of this case report is to describe the esthetic rehabilitation of a darkened central incisor in a maxillary anterior region that had irregular gingival contours, multiple composite resin restorations, and unsatisfactory tooth shapes. Harmony was restored through periodontal recontouring surgery, placement of a lithium disilicate crown (consisting of a veneer cemented to a coping) on the darkened central incisor, and placement of lithium disilicate veneers on the other maxillary anterior teeth.


Assuntos
Porcelana Dentária , Estética Dentária , Humanos , Cerâmica , Coroas , Resinas Compostas , Coroa do Dente , Facetas Dentárias
12.
Anim Reprod ; 20(3): e20220124, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37795199

RESUMO

Fetal programming suggests that maternal stimulation and nutrition during the period of fetal development can program the progeny. Conjugated linoleic acid (CLA), an isomer of linoleic acid, has been characterized in several aspects, but few studies have been performed on its involvement in reproduction and fetal programming. The aim of this study was to evaluate the F1, F2 and F3 progeny of female mice supplemented with CLA during the pregestational and gestational periods with respect to biometric and reproductive parameters, as well as ovarian morphophysiology. The F1 progeny of mothers supplemented with CLA exhibited stable weight gain, while the F2 progeny showed no effects (P=0.0187 and P=0.0245, respectively). A reduction in Lee's Index was observed in both generations at the second post-weaning evaluation week in the animals treated with CLA (P=0.0100 and P=0.0078, respectively). The F2 generation showed an increase in the anogenital index in both sexes of the animals treated with CLA (P= 0.0114 and P<0.0001, female and male respectively). CLA administration to mothers did not affect any of the following in their progeny: ovarian follicle mobilization (P>0.05), follicle number (P>0.05) and the integrated density of the lipid content of oocytes included in antral follicles (P>0.05). This study evaluated the use of CLA in mothers and found that it did not affect the progeny regarding murine reproductive performance, suggesting that this supplement can be used safely.

13.
Plants (Basel) ; 12(10)2023 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-37653945

RESUMO

Selenium uptake and its content in soybean grains are affected by Se application methods. This study evaluated the impact of Se foliar application combined with a multi-nutrient fertilizer (MNF) on soybean, establishing a Se threshold to better understand the relationship between Se content in grains and yield of two genotypes (58I60 Lança and M5917). Two trials were conducted in a 4 × 2 factorial design: four Se rates (0, 10, 40, 80 g Se ha-1) and two methods of foliar Se application (Se combined or not with MNF). Foliar fertilizers were applied twice, at phenological stages of beginning of pod development and grain filling. Grain yield increased with the application of MNF, yet Se rates increased Se contents linearly up to 80 g Se ha-1, regardless of the use of MNF. Lança and M5917 genotypes had grain Se critical thresholds of 1.0 and 3.0 mg kg-1, respectively. The application of Se favored higher contents of K, P, and S in grains of genotype Lança and higher contents of Mn and Fe in grains of genotype M5917. Our findings highlight the importance of addressing different Se fertilization strategies as well as genotypic variations when assessing the effects of Se on soybean yield and grain quality.

14.
Int. j. odontostomatol. (Print) ; 17(3): 356-371, sept. 2023. ilus, tab, graf
Artigo em Inglês | LILACS | ID: biblio-1514380

RESUMO

The present study aimed to review the literature on the main complications of antineoplastic therapies and the degree of knowledge of dental surgeons about these complications. A bibliographic search was conducted in the main health databases PUBMED (www.pubmed.gov) and Scholar Google (www.scholar.google.com.br), in which studies published from 1987 to 2023 were collected. Laboratory studies, case reports, systematic and literature reviews, which were developed in living individuals, about the main neoplastic genes and their relationship with the cells of individuals affected by neoplasms in the head and neck region, and studies on the care with this group of patients, were included. Therefore, articles that did not deal with neoplasm and the main complications of antineoplastic therapies were excluded. Neoplasm is a clonal disorder, caused by mutations, resulting from changes in the genetic structure of cells. Each healthy cell has instructions on how to grow and divi de. In the presence of any error in these instructions (mutation), it can result in a diseased cell that, when proliferating, may cause a tumor. Countless knowledge has been accumulated over the years on the main characteristics of neoplasms, whether they are cancer cell biology, carcinogenesis mechanism, neoplasms of the maxillofacial system and sequels of antineoplastic treatments. In this context, methods have been developed that offer a better quality of life for patients diagnosed with this pathology, as well as preventive vaccine models that may, in the not too distant future, contribute to this goal to be successfully achieved.


El presente estudio tuvo como objetivo revisar la literatura sobre las principales complicaciones de las terapias antineoplásicas y el grado de conocimiento de los odontólogos sobre este abordaje. Se realizó una búsqueda bibliográfica en las principales bases de datos de salud PUBMED (www.pubmed.gov) y Scholar Google (www.scholar.google.com.br), en la que se recopilaron estudios publicados entre 1987 y 2023. Fueron incluidos estudios de laboratorio, relatos de casos, revisiones de la literatura y revisiones sistemáticas, desarrolladas en individuos vivos, que incluyeran los principales genes neoplásicos y su relación con las células de individuos afectados por neoplasias en la cabeza y el cuello. También, se tuvieron en cuenta estudios relacionados con la atención a este grupo de pacientes. La neoplasia es un trastorno clonal, causado por mutaciones, como resultado de cambios en la estructura genética de las células. Cada célula sana tiene instrucciones sobre cómo crecer y dividirse. En presencia de cualquier error en estas instrucciones (mutación), puede provocar una célula alterada que, al proliferar, puede causar un tumor. Se han acumulado innumerables conocimientos a lo largo de los años sobre las principales características de las neoplasias, ya sea sobre biología de células cancerosas, el mecanismo de la carcinogénesis, la neoplasias del sistema maxilofacial y las diferentes secuelas de tratamientos antineoplásicos. En este contexto, se han desarrollado métodos que ofrecen una mejor calidad de vida para los pacientes diagnosticados con esta patología, así como modelos de vacunas preventivas que, en un futuro no muy lejano, pueden contribuir a alcanzar este objetivo con éxito.


Assuntos
Humanos , Assistência Odontológica , Genes Neoplásicos/genética , Neoplasias de Cabeça e Pescoço/genética
15.
Heliyon ; 9(6): e16935, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37484370

RESUMO

It is hard for medical students to recognize and understand the clinical presentation of systemic connective tissue diseases (SCTDs). In this study, we aimed to review the immune mechanisms of the main SCTDs and to propose a classification system focused on the student and based on each immune dysfunction's clinical phenotype. The search involved the MEDLINE database and included the terms "systemic lupus erythematosus," "antiphospholipid syndrome," "inflammatory myopathies," "rheumatoid arthritis," "Sjögren's syndrome" or "systemic sclerosis" and "pathogenesis," and "immunology" or "mechanism of disease." Systemic lupus erythematosus (SLE) is a prototypic immune-complex disease with a tendency toward vascular injury. Antiphospholipid syndrome (APS) is a diffuse immune-mediated thrombotic vasculopathy. In inflammatory myopathies (IMs), muscle inflammation leading to muscle weakness is the cardinal manifestation. Rheumatoid arthritis (RA) is a unique form of erosive and destructive polyarthritis. Sjögren's syndrome (SS) causes sicca symptoms due to infiltration of the exocrine glands. Disseminated fibrosis in systemic sclerosis (SSc) is caused by vascular injury with excessive fibroblast activation. After the review, we created a focus group involving all the authors to group the diseases according to their pathogenesis and clinical phenotype. Our group agreed that SCTDs can be divided in 3 groups based on the preferential clinical presentation and immune dysfunction: 1) vasculopathic features (SLE and APS), 2) tissue inflammation (IMs, RA, and SS), and 3) tissue fibrosis (SSc). In synthesis, we suggest that clustering SCTDs in groups based on clinical phenotype and presumptive immune dysfunction instead of ordering autoantibodies randomly can help students understand the diseases.

16.
Plants (Basel) ; 12(13)2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37447116

RESUMO

Water deficit inhibits plant growth by affecting several physiological processes, which leads to the overproduction of reactive oxygen species (ROS) that may cause oxidative stress. In this regard, iodine (I) is already known to possibly enhance the antioxidant defense system of plants and promote photosynthetic improvements under adverse conditions. However, its direct effect on water deficit responses has not yet been demonstrated. To verify the efficiency of I concerning plant tolerance to water deficit, we exposed soybean plants to different concentrations of potassium iodide (KI) fed to pots with a nutrient solution and subsequently submitted them to water deficit. A decline in biomass accumulation was observed in plants under water deficit, while exposure to KI (10 and 20 µmol L-1) increased plant biomass by an average of 40%. Furthermore, exposure to KI concentrations of up to 20 µM improved gas exchange (~71%) and reduced lipid peroxidation. This is related to the higher enzymatic antioxidant activities found at 10 and 20 µM KI concentrations. However, when soybean plants were properly irrigated, KI concentrations greater than 10 µM promoted negative changes in photosynthetic efficiency, as well as in biomass accumulation and partition. In sum, exposure of soybean plants to 10 µM KI improved tolerance to water deficit, and up to this concentration, there is no evidence of phytotoxicity in plants grown under adequate irrigation.

17.
Int. j. odontostomatol. (Print) ; 17(2): 174-185, jun. 2023. ilus, tab
Artigo em Inglês | LILACS | ID: biblio-1440356

RESUMO

This in silico study aimed to evaluate the biomechanical behavior of a full-arch implant-supported prosthesis on titanium and zirconia monotype implants. A 3D mandible containing 1.0 mm thick cortical and cancellous bone was modeled. Four dental implants (3.3 x 10 mm) were inserted into the jaw model in each model. The implants consisted of Titanium (Ti-S group) and Zirconia Monotype/one-piece (Zr-S group). Fixed full-arch implant-supported prostheses were cemented onto the implant. The models were exported to the analysis software and divided into meshes composed of nodes and tetrahedral elements. All materials were considered isotropic, elastic, and homogeneous. Therefore, all contacts were considered bonded, the mandible model was fixed in all directions, applying a static structural axial load of 300 N on the bottom of the fossa of the left mola r teeth. Microstrain and von-Mises stress (MPa) were adopted as failure criteria. Comparable stress and strain values were shown in the peri-implant bone for both groups. However, the Ti-S group presented a lower stress value (1,155.8 MPa) than the Zr-S group (1,334.2 MPa). Regarding bone tissues, the Ti-S group presented 612 µε and the Zr-S group presented 254 µε. The highest strain peak was observed in bone tissues around the implant closer to the load for both groups. Evaluating monotype zirconia and titanium implants, it is suggested that the greater the rigidity of the implant, the greater the concentration of internal stre sses and the less dissipation to the surrounding tissues. Therefore, monotype ceramic implants composed of yttrium-stabilized tetragonal polycrystalline zirconia may be a viable alternative to titanium implants for full-arch prostheses.


El objetivo de este estudio in silico fue evaluar el comportamiento biomecánico de una prótesis implanto soportada de arcada completa sobre implantes monotipo de titanio y zirconia. Se modeló una mandíbula en 3D que contenía tejido óseo cortical y esponjoso de 1,0 mm de espesor. En cada modelo, se insertaron cuatro implantes dentales (3,3 x 10 mm) en el modelo de mandíbula. Los implantes consistieron en Monotipo de Titanio y Zirconia. Sobre el implante se cementaron prótesis implanto soportadas de arcada completa fija. Los modelos se exportaron al software de análisis y se dividieron en mallas compuestas por nodos y elementos tetraédricos. Todos los materiales se consideraron isotrópicos, elásticos y homogéneos. Por lo tanto, todos los contactos se consideraron cementados, el modelo mandibular se fijó en todas las direcciones, aplicando una carga vertical estructural estática de 300 N en el fondo de la fosa de los dientes molares izquierdos. Se seleccionaron la microesfuerzo y la tensión de Von-Mises (MPa) como criterios de falla. Se mostraron valores de tensión y deformación comparables en el hueso periimplantario para ambos grupos. Sin embargo, el grupo Ti-S presentó un valor de estrés menor (1.155,8 MPa) que el grupo Zr-S (1.334,2 MPa). En cuanto a los tejidos óseos, el grupo Ti-S presentó 612 µε y el grupo Zr-S presentó 254 µε. La mayor concentración de deformación en el tejido óseo se observó en los tejidos alrededor del implante más cerca de la carga para ambos grupos. Al evaluar los implantes monotípicos de zirconia y titanio, se sugiere que cuanto mayor sea la rigidez del implante, mayor será la concentración de tensiones internas y menor la disipación a los tejidos circundantes. Por lo tanto, los implantes cerámicos monotipo compuestos de zirconia policristalina tetragonal estabilizada con itrio pueden ser una alternativa viable a los implantes de titanio para prótesis de arcada completa.


Assuntos
Implantes Dentários , Materiais Dentários , Estresse Mecânico , Fenômenos Biomecânicos , Análise de Elementos Finitos , Mandíbula/diagnóstico por imagem
18.
Int. j. odontostomatol. (Print) ; 17(2): 142-154, jun. 2023. tab, ilus
Artigo em Inglês | LILACS | ID: biblio-1440352

RESUMO

The present study proposed to describe, through a literature review, the use of new therapeutic management which allows for offering a better quality of life to individuals affected by these pathologies. A bibliographic search was conducted in the main health databases PUBMED (www.pubmed.gov) and Scholar Google (www.scholar.google.com.br), in which studies published from 1987 to 2023 were collected. In the first stage, the list of retrieved articles was examined by reading the titles and abstracts. In the second stage, the studies were selected by reading the full contents. Two authors (JDMM and DAQ) performed stages 1 and 2. Experimental, clinical, case-control, randomized controlled, and laboratory cohort studies, case reports, systematic reviews, and literature reviews, which were developed in living individuals, were included. Therefore, articles that did not deal with the subject in question, letters to the editor, opinion articles, duplicated literature in databases, and literature that did not address the variables under study, we re excluded. Contemporary dentistry uses alternative treatments capable of improving the patient's condition since a cure is not always possible. Therefore, the possibility of improving the quality of life becomes an important point to be reached. Evidence-based healthcare has made great advances in recent decades, especially in the areas of orofacial pain, TMD, and occlusion, especially related to orthodontic, prosthetic, and restorative care.


En el presente estudio se propuso describir, a través de una revisión bibliográfica, el uso de nuevos manejos terapéuticos que permitan brindar una mejor calidad de vida a los individuos afectados por estas patologías. Se realizó una búsqueda bibliográfica en las principales bases de datos de salud PUBMED (www.pubmed.gov) y Scholar Google (www.scholar.google.com.br), en las que se recopilaron estudios publicados entre 1987 y 2023. En la primera etapa, se examinó la lista de artículos recuperados mediante la lectura de los títulos y resúmenes. En la segunda etapa, los estudios fueron seleccionados mediante la lectura del contenido completo. Dos autores (JDMM y DAQ) realizaron las etapas 1 y 2. Se incluyeron estudios de cohortes experimentales, clínicos, de casos y controles, controlados aleatorios y de laboratorio, informes de casos, revisiones sistemáticas y revisiones de la literatura, que se desarrollaron en individuos vivos. Por lo tanto, se excluyeron artículos que no trataran el tema en cuestión, cartas al editor, artículos de opinión, literatura duplicada en bases de datos y literatura que no abordara las variables en estudio. La odontología contemporánea utiliza tratamientos alternativos capaces de mejorar el estado del paciente, ya que no siempre es posible la curación. Por lo tanto, la posibilidad de mejorar la calidad de vida se convierte en un objetivo importante. La atención médica basada en la evidencia ha logrado grandes avances en las últimas décadas, especialmente en las áreas de dolor orofacial, TMD y oclusión, especialmente en relación con la atención de ortodoncia, prótesis y restauración.


Assuntos
Humanos , Dor Facial/terapia , Transtornos da Articulação Temporomandibular/terapia , Terapia por Acupuntura/métodos , Estimulação Elétrica Nervosa Transcutânea/métodos
19.
J Esthet Restor Dent ; 35(6): 927-936, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37203879

RESUMO

PURPOSE: The aim of this study was to evaluate staining layer behavior applied to high-translucency zirconia (YZHT), feldspathic ceramics (FD), and zirconia-reinforced lithium silicate (ZLS) surfaces against different antagonists. METHODS AND MATERIALS: Monolithic ceramic discs (n = 120) (ø 12 mm; thickness, 1.2 mm; ISO 6872) were obtained, 30 from YZHT and FD, and 60 from ZLS CAD/CAM blocks (staining layer applied before or after the crystallization procedure). The specimens were divided into 12 subgroups (n = 10) according to the antagonists: steatite, polymer-infiltrated ceramic, or zirconia. Mechanical cycling (1.5 × 104 cycles; 15 N; horizontal displacement, 6 mm; 1.7 Hz) and flexural strength tests (1 mm/min-1000 kg cell) were performed. The differences between final and initial roughnesses (Ra, Rz, and Rsm), the mass loss, and the flexural strength data were individually analyzed by two-way ANOVA and Tukey's test (α = 0.05). RESULTS: The roughnesses of all ceramics did not present a statistically significant difference before wear simulation: Ra (p = 0.3348), Rz (p = 0.5590), and Rsm (p = 0.5330). After the wear simulation, the Ra parameter was not affected by an interaction between ceramic and antagonist (p = 0.595). The Rz and Rsm parameters were affected only by the antagonist pistons (both, p = 0.000). The ceramics used in this study showed statistically significant differences in mass loss after the wear test (p < 0.0001). The additional firing (2 steps) of the ZLS2 led to a higher lost mass quantity. CONCLUSION: All ceramics presented similar initial roughnesses and similar roughnesses after the wear simulation. The zirconia antagonist showed better performance against ceramics with high crystalline content. CLINICAL SIGNIFICANCE: It is clear that restorative materials must be carefully selected by dental practitioners according to indications, properties, and antagonists. The steatite antagonist, that is, an enamel analog, showed better performance against vitreous ceramics, while the zirconia antagonist showed better performance against ceramics with high crystalline content. Wear affects the surface roughnesses of the ceramics. Additional firing for the staining of the zirconia-reinforced lithium silicate ceramic led to a greater loss of mass.


Assuntos
Porcelana Dentária , Lítio , Humanos , Porcelana Dentária/química , Odontólogos , Teste de Materiais , Papel Profissional , Cerâmica/química , Zircônio/química , Silicatos , Propriedades de Superfície , Desenho Assistido por Computador
20.
Rev Col Bras Cir ; 50: e20233442, 2023.
Artigo em Inglês, Português | MEDLINE | ID: mdl-36995835

RESUMO

INTRODUCTION: breast cancer is the cancer with the highest incidence in women in Brazil, representing 29.7% of all cancers. More than two thirds of women with breast cancer show expression for hormone receptors, and in these cases, hormone therapy with tamoxifen is indicated, which may represent a risk factor for the development of endometrial cancer (four-fold greater relative risk). OBJECTIVE: this study aimed to evaluate the association of tamoxifen and the development of endometrial disturbances and to assess possible other associated risk factors. PATIENTS AND METHOD: a total of 364 breast cancer patients were evaluated, 286 who used tamoxifen and 78 who did not use this hormone therapy. Results: patients who used tamoxifen had a mean follow-up time of 51.42 months similar to those without hormone therapy (p=0.081). A total of 21 (7.3%) women who used tamofixen and no cases among women without hormone therapy presented endometrial changes during follow-up (p=0.01). Despite information regarding obesity was available for only 270 women, obesity was also significantly associated with the development of endometrial changes (p=0.008). CONCLUSION: furthermore, the association between tamofixen and endometrial changes remained significant (p=0.039) after adjusting for obesity.


Assuntos
Neoplasias da Mama , Neoplasias do Endométrio , Humanos , Feminino , Masculino , Neoplasias da Mama/patologia , Estudos Retrospectivos , Tamoxifeno/efeitos adversos , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/induzido quimicamente , Fatores de Risco , Obesidade/complicações , Hormônios
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