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1.
When dealing with patients with periodontal disease of variable severities, dentists must often choose between treating and restoring the involved tooth or indicating its extraction. Different criteria have been adopted in this decision-making process. The purpose of this study was to evaluate the criteria adopted by dentists to indicate the extraction of teeth with periodontitis. Dentists were interviewed at their private practices in three cities of the state of Rio Grande do Sul, Brazil. The evaluated criteria included severity of attachment loss, tooth mobility, furcation involvement, prosthetic planning, periodontal-endodontic lesion, possible systemic involvement due to the presence of periodontitis, referral to a periodontist for evaluation, radiographic bone loss greater than 50%, presence of extensive caries, socio-economic and cultural status of the patient, among others. The most often adopted criteria to indicate the extraction of periodontally affected teeth were the presence of mobility (37.5%), severity of attachment loss (24.3%) and radiographic bone loss greater than 50% (21.2%). The results of the present study demonstrated the difficulties faced by dentists to indicate the extraction of teeth with severe attachment loss, in addition to the establishment of an adequate prognosis. Aspects associated with the past disease were still the most often reported to indicate the extraction of teeth for periodontal reasons.  相似文献   
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Myofibroblasts are hybrid-phenotype differentiated cells in between fibroblasts and smooth muscle cells. Due to their contractile features and ability to synthesize extracellular matrix components, cytokines, proteases, and proangiogenic factors, myofibroblasts have been implicated in the pathogenesis of fibrocontractive diseases and in the progression of many tumors, including oral squamous cell carcinoma (SCC).ObjectiveTo perform a literature review on the origin of myofibroblasts, their main morpho-physiological and immunohistochemical aspects, and to discuss the correlations with oral SCC.MethodA search was made on the PUBMED database to select the main papers in the literature in English related to the subject, published between January 1991 and December 2011.ConclusionMyofibroblasts are an important component of the stroma of oral SCCs, although they are not present in all tumors. Abundant presence of myofibroblasts may be associated with local disease recurrence and decreased patient survival. However, given the relatively limited number of studies on the subject, further research is needed to clarify the molecular mechanisms by which myofibroblasts influence the biological behavior of oral SCC.  相似文献   
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A decade has passed since we first reviewed the epidemiology of periodontal diseases in Latin America. At that time, lack of population‐based studies was the norm and our conclusions were based on very limited evidence. The aim of the present comprehensive review was to update and expand our previous work by providing a broad overview of Latin America and its current social, economic and demographic status and by focusing on the epidemiology of periodontal diseases in Latin American adults published in the last 15 years. The amount of periodontal epidemiological data available has increased but is still restricted to a few countries only. The scope of the literature available has also broadened to include oral health‐related quality of life and systemic interactions; however, most studies had methodological limitations that might have biased their results. In general, periodontitis was very prevalent, but severe periodontal destruction was localized. Besides being associated with well‐established risk factors, periodontitis was associated with demographics and socio‐economic factors in Latin American populations. To advance epidemiological knowledge, population‐based cross‐sectional and longitudinal studies, using appropriate methodologies, should be the future focus of the research agenda of researchers and public health planners in Latin American countries.  相似文献   
4.
Objective: To evaluate the effect of different fluoride- and calcium- and/or phosphate-containing products on their ability to prevent enamel demineralization under pH cycling conditions.

Material and methods: Enamel bovine specimens were assigned to the following groups: G1-MPP (MI Paste Plus, 0.2% NaF, Recaldent?, GC Corporation Tokyo, Japan); G2-FD (Crest? Cavity Protection, 0.243% NaF, Procter &; Gamble, USA); G3-CLP (Clinpro? 5000, 1.1% NaF, 3M ESPE, USA); and G4-CO (Control without fluoride, Silica-based dentifrice; Daudt Ltda, Brazil). The specimens were soaked in demineralizing solution for 6?h and remineralizing solution for 18?h alternatively for 10 days. The toothpaste was prepared with deionized water in a 1:3 ratio (w/v) for three minutes daily. The solutions were renewed every 48?h. After cycling, enamel changes were analysed by percentage change of SMH (%SMH) and energy-dispersive X-ray spectroscopy (EDS). The %SMH value observed for G3-CLP (2.9?±?39.2) was higher than that found in G4-CO (?13.0?±?20.7), G1-MPP (?8.9?±?20.9) and G2-FD (?3.9?±?27.1). The %SMH was similar for all treatment groups (one-way ANOVA and Tukey’s HSD; p?2+ and Ptotal in the remineralization solutions were not different among all groups (Kruskal–Wallis; p?2+ concentration in the demineralization solution was significantly lower in G1-MPP. Ca2+ concentration increased in all groups after 48?h, except for G3-CLP. The EDX quantitative analysis showed that the atomic % of elements is lower level at G4-CO.

Conclusions: The Clinpro? 5000 demonstrated having the most protective effect against demineralization; however, the % SMH was similar for all groups.  相似文献   
5.
Clinical Oral Investigations - This study aimed to develop a porous chitosan–calcium–aluminate scaffold (CH-AlCa) in combination with a bioactive dosage of 1α,25-dihydroxyvitamin...  相似文献   
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We evaluated the influence of allelic frequency of the human leukocyte antigen (HLA) -DRB1 on the acquisition of antibody response against malaria sporozoite and merozoite peptides in patients with Plasmodium vivax malaria acquired in endemic areas of Brazil. IgG antibodies were detected by enzyme-linked immunosorbent assay against four peptides of circumsporozoite protein (CSP) (amino, carboxyl, and VK210 and VK247 repeats) and peptides of merozoite surface protein 1 (MSP-1), apical membrane antigen 1 (AMA-1), and Duffy-binding protein (DBP). We found an association between HLA-DR3 and HLA-DR5 alleles and lack of antibody response to CSP amino terminal, as well as an association between HLA-DR3 and the highest antibody response to MSP1 (Pv200L). In conclusion, we suggest a potential regulatory role of the HLA-DRB1 alleles in the production of antibodies to a conserved region of P. vivax CSP and MSP1 in Brazilian population exposed to malaria.  相似文献   
10.
Tall stature is a common feature of both Marfan syndrome and XYY syndrome. Differential diagnosis between these entities has important prognostic implications. We report the case of a 21-year-old young man with a previously known diagnosis of XYY syndrome, in whom the identification of a fibrilin-1 mutation was determinant to establish an appropriate diagnosis, medical follow-up, and genetic counselling.  相似文献   
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