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391.
Background: Prediction of periodontitis development is challenging. Use of oral health–related data alone, especially in a young population, might underestimate disease risk. This study investigates accuracy of oral, systemic, and socioeconomic data on estimating periodontitis development in a population‐based prospective cohort. Methods: General health history and sociodemographic information were collected throughout the life‐course of individuals. Oral examinations were performed at ages 24 and 31 years in the Pelotas 1982 birth cohort. Periodontitis at age 31 years according to six classifications was used as the gold standard to compute area under the receiver operating characteristic curve (AUC). Multivariable binomial regression models were used to evaluate the effects of oral health, general health, and socioeconomic characteristics on accuracy of periodontitis development prediction. Results: Complete data for 471 participants were used. Periodontitis classifications with lower thresholds yielded superior predictive power. Calculus, pocket, or bleeding presence at age 24 years separately presented fair accuracy. Accuracy increased using multivariable models; for example, the Beck et al. classification AUC from 0.59 to 0.75 combining proportion of teeth with calculus, bleeding, or pocket with income; number of lost teeth; sex; education; people living in the house; prosthetic needs; or number of decayed, missing, or filled teeth (DMFT). Proportion of teeth with pocket, bleeding, or calculus; number of DMFT; toothbrushing frequency; blood pressure; sex; and income were most frequently associated. Conclusions: Choice of classification might have an impact on accuracy to predict periodontitis occurrence. Regardless of the classification, predictive value for development of periodontitis in young adults might be increased by combining periodontal information, sociodemographic information, and general health history.  相似文献   
392.
Aim: The aim of the study was to evaluate the prevalence of dental pain in preschool children and its association with socioeconomic, demographic, clinical, and behavior variables. Subjects and Methods: The study was nested in a population-based birth cohort from Pelotas, Brazil, started in 2004. A sample of 1,129 children aged 5 years was dentally examined, and their mothers were interviewed. Exploratory variables included demographics, socioeconomic status, mothers' oral health status and associated behaviors, and caries in primary teeth. Data were analyzed using multivariable Poisson regression. Results: The prevalence of dental pain was 16.5% (95% CI: 14.4-18.8). Multivariate analysis showed that dark-skinned children (prevalence ratio, PR = 1.6, 95% CI: 1.1-2.4) from low socioeconomic level (PR 1.9, 1.2-3.0) whose mothers had less than 4 years of education (PR 1.9, 1.0-3.6), from mothers with less than 10 teeth in at least one arch (PR 1.7, 1.2-2.5) and less than 10 in two arches (PR 1.6, 1.0-2.6), and those with high caries prevalence at the age of 5 years (PR 4.8, 3.3-7.1) were more likely to experience dental pain. Conclusions: Unrestored caries is the main factor associated with dental pain in childhood. Socioeconomic aspects and family context in which dental pain occurs should also be taken into account when dental pain preventive measures are implemented.  相似文献   
393.
This study evaluated in vitro and in situ the potential adverse effects of 10% carbamide peroxide on human enamel using microhardness, calcium loss and surface morphology analysis. Twenty-four enamel slices (4 mm2) were obtained from recently extracted premolars. The specimens were polished under water-cooling down to 1,200-grade sandpaper. After initial microhardness readings (100 g), the specimens were randomly divided into two groups for in situ and in vitro conditions. The specimens were covered with 10% carbamide peroxide for eight hours. After removing the bleaching gel, the in vitro specimens were stored in deionized water and the in situ specimens, included in an intra-oral appliance, were placed in the oral cavity of four volunteers. These cycling sequences took place for 14 days. Upon conclusion of the bleaching treatment, new microhardness readings were performed on all specimens. Calcium dosage was assessed from the bleaching gel collected after initial exposure on day one, then from gel collected between days two and seven and gel collected between day eight and 14 using an atomic absorption spectrophotometer. Surface morphology was observed from two non-treated control specimens and two specimens of each experimental bleached group under SEM evaluation. Statistical analysis (ANOVA and Tukey tests) disclosed that specimens bleached in situ showed similar microhardness to unbleached specimens and had statistically higher (p < 0.01) hardness than in vitro bleached specimens. The loss of calcium in the in vitro situation at 14 days was 2.5 times higher than the in situ condition. SEM micrographs demonstrated that surface alterations were more pronounced in the in vitro condition. The adverse effects of carbamide peroxide on enamel were evident in specimens bleached in vitro but were not seen in situ. The presence of saliva could prevent the demineralizing effect of bleaching gel in situ.  相似文献   
394.
The aim of this study was to evaluate the influence of caries-detecting dyes on the microleakage of adhesive materials. Sixty cubic class V cavities were prepared on buccal and lingual surfaces of 30 human third molars. Coronal margins were located in enamel and gingival margins in cementum. The teeth were randomly divided into six groups of ten restorations each. Cavities were restored with an adhesive system (Single Bond, 3M ESPE, St. Paul, Minn., USA), a compomer (F2000, 3M ESPE), or a composite resin (Z100, 3M ESPE) according to the manufacturer's directions. Acid red dye (Seek, Ultradent, South Jordan, Ut., USA) and basic fuchsin dye (Vide Cárie, Inodon, Porto Alegre, Brazil) were tested. Control groups were prepared without the use of dyes. After 7 days of storage in distilled water, the restorations were polished and the teeth were subjected to thermal cycling followed by immersion in 2% methylene blue. The teeth were sectioned, and microleakage scores were evaluated under magnification (40x). Data were submitted to statistical analysis using the nonparametric Kruskal-Wallis test. A statistically significant difference ( P<0.05) in microleakage was found between the materials in cementum (Z100>F2000) but not in enamel. Control and experimental groups using dyes showed similar results. It was concluded that dyes for caries detection did not increase microleakage of the adhesive materials tested.  相似文献   
395.
Heparin-induced thrombocytopenia (HIT) is an increasingly common clinical finding in patients presenting for cardiac transplantation. Bivalrudin, a reversible direct thrombin inhibitor, is a molecular anti-coagulant with short half-life and the potential for removal by intraoperative hemofiltration. Herein we describe the dosing and intraoperative management of bivalrudin anti-coagulation in a patient undergoing urgent cardiac transplantation in the context of recently diagnosed HIT.  相似文献   
396.
Lyme disease, the most commonly reported tick-borne infection in North America, is caused by infection with the spirochete Borrelia burgdorferi. Although an accurate clinical diagnosis can often be made based on the presence of erythema migrans, in research studies microbiologic or molecular microbiologic confirmation of the diagnosis may be required. In this study, we evaluated the sensitivity of 5 direct diagnostic methods (culture and nested polymerase chain reaction [PCR] of a 2-mm skin biopsy specimen, nested PCR and quantitative PCR (qPCR) performed on the same 1-mL aliquot of plasma and a novel qPCR-blood culture method) in 66 untreated adult patients with erythema migrans. Results of one or more of these tests were positive in 93.9% of the patients. Culture was more sensitive than PCR for both skin and blood, but the difference was only statistically significant for blood samples (P<0.005). Blood culture was significantly more likely to be positive in patients with multiple erythema migrans skin lesions compared to those with a single lesion (P=0.001). Positive test results among the 48 patients for whom all 5 assays were performed invariably included either a positive blood or a skin culture. The results of this study demonstrate that direct detection methods such as PCR and culture are highly sensitive in untreated adult patients with erythema migrans. This enabled microbiologic or molecular microbiologic confirmation of the diagnosis of B. burgdorferi infection in all but 4 (6.1%) of the 66 patients evaluated.  相似文献   
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