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1.
Public Health Genomics ; : 1-14, 2022 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-35944511

RESUMO

INTRODUCTION: Ashkenazi Jewish (AJ) individuals face a 1 in 40 (2.5%) risk of having a BRCA mutation, which is 10 times the general population risk. JScreen launched the PEACH BRCA Study, a telehealth-based platform for BRCA education and testing, with the goal of creating an effective model for BRCA testing in low-risk AJ individuals who do not meet national testing criteria. Other goals were to determine the rate of BRCA mutations in this group, to assess the adequacy of screening for the 3 common AJ founder mutations only, and to assess satisfaction with the telehealth model to help inform a national launch of a broader cancer genetic testing program. METHODS: Criteria for participation included those who were AJ, resided in the metro-Atlanta area, were aged 25 and older, and had no personal or close family history of BRCA-related cancers. Pre-test education was provided through a video and written summary, followed by complimentary BRCA1/2 sequencing and post-test genetic counseling. Participants responded to pre- and post-test surveys, which assessed knowledge and satisfaction. Those who were not eligible to participate were sent genetic counseling resources and later surveyed. RESULTS: Five hundred one participants were tested and the results included 4 positives (0.8% positivity rate), 494 negatives, and 3 variants of uncertain significance. Overall satisfaction with the study process was high (96.9/100), knowledge about BRCA was high (97.5% of participants passed a pre-test knowledge quiz), and satisfaction with pre- and post-test education was high (97.9% of participants were satisfied with the pre-test video and written summary, and 99.5% felt that their post-test genetic counseling session was valuable). Many participants expressed interest in receiving broader cancer testing. CONCLUSIONS: The BRCA founder mutation rate in a low-risk AJ population was significantly lower than the previously established AJ rate of 1 in 40. It was also determined that a telehealth model for a cancer genetics program is effective and acceptable to the population tested. This study established interest in broader cancer genetic testing through a telehealth platform and suggested that testing may be successful in the Jewish community at a national level and potentially in other populations, provided that patient education and genetic counseling are adequately incorporated.

2.
J Community Genet ; 13(3): 281-292, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35486291

RESUMO

Pathogenic variants in the BRCA1 and BRCA2 (BRCA1/2) genes are associated with elevated cancer risks in men and women. Due to a founder effect, Ashkenazi Jewish individuals are at higher risk for carrying three specific BRCA1/2 pathogenic variants. There have been recent calls for population screening in this population because many carriers do not have family histories suggestive of hereditary cancer. One approach could be to integrate optional BRCA1/2 testing into routinely offered reproductive carrier screening for recessive and X-linked disorders. However, the differing goals of these types of testing (i.e., personal health risks versus family planning) raise questions about the implications for patient education and informed consent. To this end, we aimed to determine interest, attitudes, and preferences regarding integrating such testing by electronically surveying 331 Ashkenazi Jewish participants in JScreen - a national, not-for-profit, at-home carrier screening program focused on genetic risks in Jewish communities. We found that while 41% of participants had plans to pursue BRCA1/2 testing, 93% would have opted for such testing if offered as an add-on to reproductive carrier screening. This was particularly true of those with higher perceived cancer risk and more positive attitudes toward genetic testing. With respect to preferences about delivery of this service, more than 85% of participants preferred remote (telephone, print, or web-based) genetic education rather than traditional genetic counseling. These results suggest that offering optional BRCA1/2 testing within the context of reproductive carrier screening might provide opportunities for cancer prevention without overburdening scarce genetic counseling resources.

3.
J Clin Oncol ; 39(26): 2881-2892, 2021 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-34138638

RESUMO

PURPOSE: Patients with myelofibrosis who are relapsed or refractory (R/R) to Janus-associated kinase inhibitors (JAKis) have poor clinical outcomes including dismal overall survival (OS) that ranges between 13 and 16 months. Imetelstat, a telomerase inhibitor, was evaluated in patients with intermediate-2 or high-risk myelofibrosis R/R to JAKi in a phase II multicenter study (ClinicalTrials.gov identifier: NCT02426086). PATIENTS AND METHODS: Patients were randomly assigned to receive either imetelstat 9.4 mg/kg or 4.7 mg/kg intravenous once every 3 weeks. Spleen response (≥ 35% spleen volume reduction) and symptom response (≥ 50% reduction in total symptom score) rates at week 24 were coprimary end points. Secondary end points included OS and safety. RESULTS: Study enrollment was closed early, and patients treated with 4.7 mg/kg were permitted to continue treatment with 9.4 mg/kg. At week 24, spleen and symptom response rates were 10.2% and 32.2% in the 9.4-mg/kg arm and 0% and 6.3% in the 4.7-mg/kg arm. Treatment with imetelstat 9.4 mg/kg led to a median OS of 29.9 months and bone marrow fibrosis improvement in 40.5% and variant allele frequency reduction of driver mutations in 42.1% of evaluable patients. Fibrosis improvement and variant allele frequency reduction correlated with OS. Target inhibition was demonstrated by reduction of telomerase activity and human telomerase reverse transcriptase level and correlated with spleen response, symptom response, and OS. Most common adverse events on both arms were grade 3 or 4 reversible cytopenias. CONCLUSION: In this phase II study of two imetelstat doses, 9.4 mg/kg once every 3 weeks demonstrated clinical benefits in symptom response rate, with an acceptable safety profile for this poor-risk JAKi R/R population. Biomarker and bone marrow fibrosis assessments suggested selective effects on the malignant clone. A confirmatory phase III study is currently underway.


Assuntos
Inibidores Enzimáticos/administração & dosagem , Oligonucleotídeos/administração & dosagem , Mielofibrose Primária/tratamento farmacológico , Telomerase/antagonistas & inibidores , Idoso , Inibidores Enzimáticos/efeitos adversos , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oligonucleotídeos/efeitos adversos , Mielofibrose Primária/enzimologia , Mielofibrose Primária/mortalidade , Mielofibrose Primária/patologia , Recidiva , Método Simples-Cego , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
5.
J Clin Oncol ; 39(1): 48-56, 2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-33108243

RESUMO

PURPOSE: Patients with lower-risk (LR) myelodysplastic syndromes (MDS) who are RBC transfusion dependent and have experienced relapse after or are refractory to erythropoiesis-stimulating agent (ESA) have limited treatment options. High telomerase activity and human telomerase reverse-transcription expression in clonal hematopoietic cells have been reported in patients with MDS. Imetelstat, a first-in-class competitive inhibitor of telomerase enzymatic activity, targets cells with active telomerase. We report efficacy, safety, and biomarker data for patients with LR MDS who are RBC transfusion dependent and who were relapsed/refractory to ESAs. PATIENTS AND METHODS: In this two-part phase II/III study (MDS3001), the primary end point was 8-week RBC transfusion independence (TI) rate, with key secondary end points of 24-week RBC TI rate, TI duration, and hematologic improvement-erythroid. RESULTS: Data from the phase II part of the study are reported. Of 57 patients enrolled and treated (overall population), 38 were non-del(5q) and hypomethylating agent and lenalidomide naïve (subset population). The 8- and 24-week RBC TI rates in the overall population were 37% and 23%, respectively, with a median TI duration of 65 weeks. In the subset population, 8- and 24-week RBC TI rates were 42% and 29%, respectively, with a median TI duration of 86 weeks. Eight-week TI rate was observed across all subgroups evaluated. Cytogenetic and mutational data revealed a reduction of the malignant clones, suggesting disease modification activity. The most common adverse events were cytopenias, typically reversible within 4 weeks. CONCLUSION: Imetelstat treatment results in a meaningful, durable TI rate across a broad range of heavily transfused patients with LR MDS who are ineligible for or relapsed/refractory to ESAs. Biomarker analyses indicated effects on the mutant malignant clone.


Assuntos
Inibidores Enzimáticos/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Oligonucleotídeos/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/sangue , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Hematínicos/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade
6.
J Patient Rep Outcomes ; 4(1): 69, 2020 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-32851569

RESUMO

BACKGROUND: The lower-risk (low and intermediate-1 risk based on IPSS) myelodysplastic syndrome (MDS) has a negative impact on patients' health-related quality of life (HRQoL). Patient Reported Outcomes (PROs) instruments, which are used to collect patients' HRQoL data, should have established content validity in the target population to ensure that the instrument is comprehensive and comprehensible. The present study was conducted to evaluate the content validity of the Quality of Life in Myelodysplasia Scale (QUALMS) and the Functional Assessment of Cancer Therapy-Anemia (FACT-An) PRO instruments in patients with lower-risk MDS. METHODS: In this cross-sectional, qualitative study, 16 patients aged ≥18 years with lower-risk MDS, who were RBC transfusion dependent, literate and fluent in US-English were interviewed. Interviews were semi-structured comprising of two parts: concept elicitation (CE) explored symptoms and impacts important to patients, and cognitive debriefing (CD) assessed understanding and relevance of the QUALMS and FACT-An. A conceptual model was developed, which was used to map the concepts that emerged during CE onto the QUALMS and FACT-An to assess concept coverage and suitability of the instruments. RESULTS: The median age of participants was 67.5 years (range: 51-91), with half being female (n = 8). Nine (56.2%) participants had intermediate-1-risk MDS and 10 (62.5%) were relapsed or refractory to erythropoiesis-stimulating agent treatment. Fatigue/tiredness (100.0%), shortness of breath (87.5%), weakness (81.2%), and low energy (75.0%) were reported most commonly and were the most bothersome symptoms as well. Of seven high-level HRQoL domains identified, activities of daily living (n = 16, 100.0%), physical functioning (n = 15, 93.8%), emotional wellbeing (n = 13, 81.3%), social functioning (n = 12, 75.0%), sleep disturbance (n = 9, 56.3%), and impact on work (n = 9, 56.3%) were the most commonly reported. For CD, the QUALMS and FACT-An were found to be mostly relevant and very well understood; response options were easy to use, and recall period was appropriate. CONCLUSION: Both QUALMS and FACT-An demonstrated a strong face and content validity in patients with lower-risk MDS, suggesting that these instruments are appropriate for assessing HRQoL in this population.

7.
Genet Med ; 19(5): 529-536, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27735926

RESUMO

PURPOSE: The notion of offering population-based screening to the Ashkenazi Jewish (AJ) population for the BRCA1/2 founder mutations continues to gain support. A program called the BRCAcommunity initiative was designed to identify the benefits and barriers associated with implementing this screening in a clinical setting. METHODS: Interested AJ individuals were stratified into high-risk (HR) and low-risk (LR) groups based on self-reported cancer histories. Those at HR were offered traditional genetic counseling/testing; those at LR were offered group genetic counseling and subsidized AJ BRCA founder mutation testing. RESULTS: During the pilot year, 62% of initial registrants and 53% of ultimate study participants were classified into the HR group. Among the 101 HR and 88 LR study participants, 8 and 2 BRCA carriers were identified, respectively. The LR carriers would have been missed by current mechanisms. Survey responses provided insight into the motivations and fears associated with pursuing testing, the efficacy of the initiative design, and challenges that exist on multiple levels, including the community, health-care providers, and insurance coverage. CONCLUSION: Although the medical value of identifying presymptomatic BRCA carriers in Ashkenazi Jews is evident, further measures need to be taken before this effort can be accomplished on a large scale.Genet Med advance online publication 13 October 2016.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Detecção Precoce de Câncer/métodos , Judeus/genética , Adulto , Idoso , Feminino , Efeito Fundador , Triagem de Portadores Genéticos , Aconselhamento Genético , Predisposição Genética para Doença , Inquéritos Epidemiológicos , Humanos , Programas de Rastreamento , Pessoa de Meia-Idade , Projetos Piloto , Estados Unidos/etnologia
8.
Melanoma Res ; 16(6): 471-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17119447

RESUMO

We have previously demonstrated the use of pyrosequencing to investigate NRAS [neuroblastoma RAS viral (v-ras) oncogene homolog] mutations in melanoma biopsies. Here, we expanded the analysis to include BRAF (V-raf murine sarcoma viral oncogene homolog B1), another member of the Ras-Raf-mitogen-activated protein kinase (MAPK) signalling pathway, and analysed a total of 294 melanoma tumours from 219 patients. Mutations in BRAF exons 11 and 15 were identified in 156 (53%) tumours and NRAS exon 2 mutations in 86 (29%) tumours. Overall, mutations in NRAS or BRAF were found in 242 of 294 tumours (82%) and were found to be mutually exclusive in all but two cases (0.7%). Multiple metastases were analysed in 57 of the cases and mutations were identical in all except three, indicating that BRAF and NRAS mutations occur before metastasis. Association with preexisting nevi was significantly higher in BRAF mutated tumours (P=0.014). In addition, tumours with BRAF mutations showed a significantly more frequent moderate to pronounced infiltration of lymphocytes (P=0.013). NRAS mutations were associated with a significantly higher Clark level of invasion (P=0.022) than BRAF mutations. Age at diagnosis was significantly higher in tumours with NRAS mutations than in those with BRAF mutations (P=0.019). NRAS and BRAF mutations, however, did not influence the overall survival from time of diagnosis (P=0.7). In conclusion, the separate genotypes were associated with differences in several key clinical and pathological parameters, indicating differences in the biology of melanoma tumours with different proto-oncogene mutations.


Assuntos
Genes ras/genética , Melanoma/genética , Mutação/genética , Proteínas Proto-Oncogênicas B-raf/genética , Neoplasias Cutâneas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise Mutacional de DNA , DNA de Neoplasias/genética , Feminino , Genótipo , Humanos , Masculino , Melanoma/classificação , Melanoma/patologia , Pessoa de Meia-Idade , Nevo Pigmentado/patologia , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Proto-Oncogene Mas , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/secundário , Taxa de Sobrevida
9.
Pathobiology ; 72(4): 203-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16127296

RESUMO

OBJECTIVES: Several cancer prevention programmes have previously been executed using treatment of antioxidant compounds. The antioxidant N-acetyl L-cysteine (NAC), a membrane-permeable aminothiol, is a sulfhydryl reductant reducing oxidised glutathione, as well as being a precursor of intracellular cysteine and glutathione. A previous report based on the cellular response to NAC treatment showed that NAC induced a 10-fold more rapid differentiation in normal primary keratinocytes as well as a reversion of a colon carcinoma cell line from neoplastic proliferation to apical-basolateral differentiation. In order to investigate molecular events underlying the changes in proliferation and differentiation induced by NAC treatment, we performed global gene expression analysis of normal human epidermal keratinocytes in a time series. METHODS: Treated samples were compared to untreated samples through a reference design using a spotted cDNA array comprising approximately 30,000 features. B statistics was used to identify differentially expressed genes, and RT-PCR of a selected set of genes was performed to verify differential expression. RESULTS: The number of differentially expressed genes increased over time, starting with 0 at 30 min, 73 at 3 h and increasing to 952 genes at 48 h. Results of the expression analysis showed arrest of the cell cycle and an upregulation of cytoskeletal reorganisation, implicating increased differentiation. A comparison to gene ontology groups indicated downregulation of a large number of genes involved in cell proliferation and regulation of the cell cycle. CONCLUSIONS: A significant fraction of the differentially expressed genes could be classified according to their role in the differentiation process, demonstrating that NAC regulates the conversion from proliferation to differentiation at a transcriptional level.


Assuntos
Acetilcisteína/farmacologia , Ciclo Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Expressão Gênica , Queratinócitos/efeitos dos fármacos , Acetilcisteína/administração & dosagem , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , DNA Complementar , Humanos , Queratinócitos/metabolismo , Queratinócitos/ultraestrutura , Microscopia Eletrônica de Varredura , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Pele/citologia , Timidina/metabolismo , Fatores de Tempo
10.
BMC Cancer ; 5: 75, 2005 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-16001974

RESUMO

BACKGROUND: Cancer prevention trials using different types of antioxidant supplements have been carried out at several occasions and one of the investigated compounds has been the antioxidant N-acetyl-L-cysteine (NAC). Studies at the cellular level have previously demonstrated that a single supplementation of NAC induces a ten-fold more rapid differentiation in normal primary human keratinocytes as well as a reversion of a colon carcinoma cell line from neoplastic proliferation to apical-basolateral differentiation. The investigated cells showed an early change in the organization of the cytoskeleton, several newly established adherens junctions with E-cadherin/beta-catenin complexes and increased focal adhesions, all features characterizing the differentiation process. METHODS: In order to investigate the molecular mechanisms underlying the proliferation arrest and accelerated differentiation induced by NAC treatment of NHEK and Caco-2 cells in vitro, we performed global gene expression analysis of NAC treated cells in a time series (1, 12 and 24 hours post NAC treatment) using the Affymetrix GeneChip Human Genome U95Av2 chip, which contains approximately 12,000 previously characterized sequences. The treated samples were compared to the corresponding untreated culture at the same time point. RESULTS: Microarray data analysis revealed an increasing number of differentially expressed transcripts over time upon NAC treatment. The early response (1 hour) was transient, while a constitutive trend was commonly found among genes differentially regulated at later time points (12 and 24 hours). Connections to the induction of differentiation and inhibition of growth were identified for a majority of up- and down-regulated genes. All of the observed transcriptional changes, except for seven genes, were unique to either cell line. Only one gene, ID-1, was mutually regulated at 1 hour post treatment and might represent a common mediator of early NAC action. The detection of several genes that previously have been identified as stimulated or repressed during the differentiation of NHEK and Caco-2 provided validation of results. In addition, real-time kinetic PCR analysis of selected genes also verified the differential regulation as identified by the microarray platform. CONCLUSION: NAC induces a limited and transient early response followed by a more consistent and extensively different expression at later time points in both the normal and cancer cell lines investigated. The responses are largely related to inhibition of proliferation and stimulation of differentiation in both cell types but are almost completely lineage specific. ID-1 is indicated as an early mediator of NAC action.


Assuntos
Acetilcisteína/química , Diferenciação Celular/efeitos dos fármacos , Epitélio/patologia , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Cutâneas/patologia , Antioxidantes/química , Caderinas/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Linhagem da Célula , Proliferação de Células , Citoesqueleto/metabolismo , Regulação para Baixo , Epitélio/metabolismo , Genoma Humano , Humanos , Queratinócitos/citologia , Cinética , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase , Neoplasias Cutâneas/metabolismo , Fatores de Tempo , Transcrição Gênica , Regulação para Cima
11.
Cancer ; 95(2): 389-96, 2002 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-12124839

RESUMO

BACKGROUND: PEG Intron (pegylated interferon-alpha-2b [IFN-alpha-2b]; Schering-Plough, Kenilworth, NJ) has demonstrated delayed clearance and increased area under the curve compared with native IFN-alpha-2b. Studies in patients with chronic hepatitis C infection and malignancies have demonstrated both biologic and clinical activity of PEG Intron and have provided empiric data to compare the pharmacokinetics (PK) and pharmacodynamics of PEG Intron and IFN-alpha-2b. METHODS: The authors conducted a review of the available data comparing the PK and pharmacodynamic effects of PEG Intron and IFN-alpha-2b. Safety and efficacy data from Phase I/II studies of PEG Intron in patients with chronic myelogenous leukemia (CML) and solid tumors were also reviewed. RESULTS: Data from patients with chronic hepatitis C infection suggest that exposure to IFN at a PEG Intron dose of 0.25 microg/kg per week is similar to that observed after administration of IFN-alpha-2b at a dose of 3 million International Units, three times per week. PEG Intron at doses up to 6 microg/kg per week was well tolerated and demonstrated clinical activity in patients with CML and solid tumors, including metastatic melanoma and renal cell carcinoma. CONCLUSIONS: Dose intensification can be achieved safely in patients with CML and solid tumors using PEG Intron, which could improve efficacy. These results provide useful dosing guidelines to clinicians investigating the antitumor activity of PEG Intron in patients with malignancies. More data are needed to determine the optimal dose in various oncologic indications. However, these results provide a sound rationale for further investigation of PEG Intron.


Assuntos
Antineoplásicos/farmacocinética , Interferon-alfa , Interferon-alfa/farmacocinética , Polietilenoglicóis , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Relação Dose-Resposta a Droga , Esquema de Medicação , Humanos , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Proteínas Recombinantes
12.
RGO (Porto Alegre) ; 47(3): 163-4, 167-8, jul.-set. 1999. ilus, tab
Artigo em Português | LILACS, BBO | ID: lil-262596

RESUMO

Análises de alguns tipos e marcas comerciais de limalhas para restauraçöes de amálgama, foram feitas, no presente trabalho. Por meio de testes com potenciostato eletrônico foi possível obter curvas de polarizaçäo e características eletroquímicas dos materiais, com satisfatória reprodutividade. Ainda foi possível analisar restauraçöes com diferentes tratamentos superficiais, em pacientes de 14 a 40 anos de idade, durante o período de 10 anos e comparados, com os resultados obtidos por meio das curvas de polarizaçäo anódicas


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Amálgama Dentário/análise , Restauração Dentária Permanente
13.
RGO (Porto Alegre) ; 41(3): 184-6, maio-jun. 1993. ilus, tab
Artigo em Português | LILACS, BBO | ID: biblio-854934

RESUMO

Neste trabalho, foi estudado, o pico de temperatura de exotermia de polimerização dos diferentes tipos e marcas comerciais dos restauradores: Alpha Plast (M1), Durafill (M2), Estilux posterior (M3), Miradapt (M4), Prisma Fil (M5) e Alpha Light (M6). Como resultados aqui alcançados, parece lícito concluir que: 1) a reação exotérmica das RC aqui estudadas, é diferente, uma da outra, no que diz respeito, à velocidade, e essa diferença, é sentida também, nas condições, ambiente e no meio bucal, sem isolamento de campo operatório; 2) os picos de calor exotérmico, possivelmente o fim da polimerização, são diferentes, em tempo dispendido, tanto, para as marcas comerciais, como para as condições (ambiente seco e ambiente úmido); 3) o pico de temperatura, de exotermia de polimerização foi maior, nas RC quimicamente polimerizáveis, e quando no meio bucal, sem isolamento de campo operatório


Assuntos
Resinas Compostas/análise , Umidade
14.
RGO (Porto Alegre) ; 39(3): 169-70, maio-jun. 1991. ilus
Artigo em Português | LILACS, BBO | ID: biblio-854749

RESUMO

Neste trabalho, foi analisada a embebição de águas das resinas, acrílicas e compostas, nos períodos de 24h e 131.466h. totalizando 131.490 horas de teste à temperatura de 37ºC e ambiente


Assuntos
Absorção , Resinas Acrílicas , Resinas Compostas , Restauração Dentária Permanente , Restauração Dentária Temporária , Técnicas In Vitro
15.
RGO (Porto Alegre) ; 38(2): 103-5, mar.-abr. 1990. tab
Artigo em Português | LILACS, BBO | ID: biblio-854662

RESUMO

Neste trabalho, os autores fazem um estudo da estabilidade de aspectos clínicos, dos materiais usados na restauração estética: cimento de silicato, resina acrílica e resinas compostas por um período de catorze anos. Os resultados finais, foram comparados com os intermediários e pode-se perceber até inversão no comportamento de alguns restauradores estéticos e teste, SANTOS


Assuntos
Resinas Acrílicas , Resinas Compostas , Materiais Dentários , Estética Dentária , Cimento de Silicato
16.
RGO (Porto Alegre) ; 36(5): 339-42, set.-out. 1988. ilus, tab
Artigo em Português | LILACS, BBO | ID: biblio-854561

RESUMO

Com o propósito de sabermos, se é lícito aderirmos a quase 50 por cento dos profissionais de Odontologia norte-americanos (9), que usam resinas compostas na restauração de dentes posteriores é que no presente trabalho, foi estudado o comportamento clínico das restaurações de Classe I e II em pré-molares e molares. Foi dado ênfase aos desgastes no centro da restauração, isto é, na face oclusal, na crista marginal da Classe II e em toda extensão do cavo superficial. Com os resultados obtidos, parece lícito concluir que, uma marca comercial tem um melhor comportamento, porém, a sua aplicação conta com sucesso em determinados casos e quando preparos cavitários são modificados


Assuntos
Humanos , Masculino , Feminino , Adulto , Dente Pré-Molar , Resinas Compostas , Restauração Dentária Permanente , Dente Molar
17.
RGO (Porto Alegre) ; 36(3): 171-4, maio-jun. 1988. ilus, tab
Artigo em Português | LILACS, BBO | ID: biblio-854532

RESUMO

No presente trabalho, foram feitas, análises de alguns tipos e marcas comerciais de limalhas para restaurações à amálgama, após testes com um potenciostato eletrônico que situa-se hoje, entre os aparelhos que maior uso e desenvolvimento vem recebendo. Através desse aparelho, era possível obter curvas de polarização e características eletroquímicas dos materiais, com reprodutividade satisfatória. Foram analisadas, ainda, restaurações com diferentes tratamentos superficiais, em pacientes de 14 a 40 anos de idade, em um período de 2 anos e comparadas, com os resultados obtidos por meio das curvas de polarização anódicas, acima citadas


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Condicionamento Ácido do Dente
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