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971.
Swati Garg Talia Rubin John Jasek Joyce Weinstein Lisa Helburn Katherine Kaye 《Journal of the American Dental Association (1939)》2013,144(4):416-425
BackgroundDespite recommendations for children to have a dental visit by the age of 1 year, access to dental care for young children, including children enrolled in Medicaid, remains limited. The authors conducted a survey to assess the availability of dentists to see young children enrolled in Medicaid managed care (MMC) in New York City (NYC), to determine barriers to the provision of dental care to young children and, within the context of MMC, to identify strategies to facilitate the delivery of dental care to children.MethodsThe authors mailed a survey to assess the provision of dental services to young children and perceived barriers and facilitators to 2,311 general dentists (GDs) and 140 pediatric dentists (PDs) affiliated with NYC MMC. A total of 1,127 surveys (46 percent) were received. The authors analyzed the responses according to provider type, youngest aged child seen, provider’s ability to see additional children and practice location. The authors compared responses by using the χ2 test.ResultsFewer than one-half (47 percent) of GDs saw children aged 0 through 2 years. Provider type, years in practice and percentage of Medicaid-insured patients were associated significantly (P χ .005) with youngest age of child seen. Among respondents seeing children aged 0 through 2 years, PDs were significantly more likely to provide preventive therapy (P = .004) and restorative treatment (P χ .001). Additional training and access to consulting PDs were identified by GDs as potential facilitators to seeing young children.ConclusionA high proportion of NYC GDs affiliated with MMC do not see young children.Practice ImplicationsNinety-four percent of NYC MMC– affiliated dentists are GDs, but 53 percent of GD respondents did not see children aged 0 through 2 years in their practices. Improving access to dental care for young children requires changes in GDs’ practices, possibly by means of additional training and access to consulting PDs. 相似文献
972.
Objective:To evaluate the efficiency of molar distalization associated with the second and third molar eruption stage.Materials and Methods:A systematic computerized database search was conducted using several databases. Adaptations of the terms molar distalization and distalizing appliances were used. The reference lists of all the selected articles were also searched for any potential articles that might have been missed in the electronic search. The data provided in the selected publications were grouped and analyzed in terms of molar distalization with respect to various eruption stages of maxillary second and third molars.Results:Out of the 13 initially identified articles only four fulfilled the final selection criteria. Three of the four studies showed no statistical significance in linear molar distalization based on the eruptive stage of the second and/or third molars, while one study found that the amount of distal movement of the first molars was significantly greater in the group with unerupted second molars. Only one study found that the amount of molar tipping that occurred as a result of distalization was related to the eruption stage of the maxillary molars. Similarly, three of the four studies found that molar distalization time was not significantly affected by eruption of the second or third molars.Conclusion:The effect of maxillary second and third molar eruption stage on molar distalization—both linear and angular distalization—appears to be minimal. This conclusion is only based on low–level of evidence clinical trials. The large variability in the outcomes should be considered clinically. 相似文献
973.
Vivian Bradaschia-Correa Inmaculada Casado-Gomez Mariana Matheus Moreira Lorraine Braga Ferreira Victor E. Arana-Chavez 《Archives of oral biology》2013
Introduction
During root formation, Smad-4 plays a key role during the epithelial–mesenchymal interactions and the Hertwig's epithelial root sheath (HERS) apical proliferation. The root formation and eruption of rat molars is impeded by alendronate treatment due to the inhibition of bone resortion by this drug. The present study aimed to examine the structures affected in the developing root and immunodetect the presence of Smad-4 in rats treated with alendronate.Methods
Newborn Wistar rats were daily injected 2.5 mg/kg alendronate (ALN) during 9, 12 and 30 days. The controls (CON) were injected with saline. The maxillae were fixed and embedded in paraffin or Spurr resin. Paraffin sections were incubated in Smad-4 antibody that was labelled with DAB. The ultrathin sections were examined in a transmission electron microscope.Results
In ALN, a short portion of root dentine was formed; the epithelial diaphragm (ED) and the dental follicle (DF) were disorganized by the contact of bone trabeculae. The (CON) molar roots developed normally. Smad-4 labelling was detected in the cytoplasm of fibroblasts and cementoblasts adjacent to the cementum in CON; in ALN group, few ED cells presented weak immunolabelling. Ultrastructurally, the ED and DF appeared disrupted due to the presence of thin bone trabeculae between its cells. It resulted in the lack of apical proliferation of HERS and, consequently, arrest of root formation.Conclusion
The immunodetection of Smad-4 in the DF cells of ALN specimens indicates that the signalling for the differentiation of these cells into cementum-forming fibroblasts and cementoblasts occurs, despite the impairment of root elongation. 相似文献974.
975.
Elliot Nacke MD Nikko Ramos BS Spencer Stein BS Lorraine Hutzler BA Joseph A. Bosco III MD 《Clinical orthopaedics and related research》2013,471(2):569-573
Background
The episode-of-care concept promulgated by the federal government requires hospitals to assume the cost burden for all care rendered up to 30 days after discharge, including all readmissions occurring in that time. Although surgical site infections (SSIs) are a leading cause of readmission after total joint arthroplasties (TJA) and spine surgery, it is unclear whether these readmissions occur relative to the 30-day period.Questions/Purposes
We determined whether (1) most readmissions for SSIs occurred in 30 days, (2) the type of procedure performed affected the timing of readmission, and (3) the type of infecting organism influenced the timing of readmission.Methods
From our hospital database we identified 91 patients treated with elective TJAs and spine surgery from 2007 through 2010 who were readmitted with SSIs. Of the 91 patients, 46 had undergone spine surgery and 45 had TJAs. For each of these readmissions, we determined the type of surgery, the length of time from initial discharge to readmission, and the type of infecting organism.Results
Readmissions after spine surgery were more likely to occur within 30 days of discharge (80.4% for spine, 58.3% for TJAs). In the TJA cohort, there was a trend toward readmissions occurring within 30 days of discharge more often in the THA subset. We identified no correlation between type of infecting organism and timing of readmission.Conclusions
With the episode-of-care model, SSIs pose a substantial cost burden for hospitals since the majority would be included in the 30-day period included in the bundled reimbursement. 相似文献976.
977.
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979.
980.
Ann V. Schwartz Eric Vittinghoff Karen L. Margolis Lesley M. Scibora Lisa Palermo Walter T. Ambrosius Trisha F. Hue Kristine E. Ensrud 《Calcified tissue international》2013,92(5):477-486
Factors that contribute to bone fragility in type 2 diabetes are not well understood. We assessed the effects of intensive glycemic control, thiazolidinediones (TZDs), and A1C levels on bone geometry and strength at the radius and tibia. In a substudy of the Action to Control Cardiovascular Risk in Diabetes trial, peripheral quantitative computed tomographic (pQCT) scans of the radius and tibia were obtained 2 years after randomization on 73 participants (intensive n = 35, standard n = 38). TZD use and A1C levels were measured every 4 months during the trial. Effects of intervention assignment, TZD use, and A1C on pQCT parameters were assessed in linear regression models. Intensive, compared with standard, glycemic control was associated with 1.3 % lower cortical volumetric BMD at the tibia in men (p = 0.02) but not with other pQCT parameters. In women, but not men, each additional year of TZD use was associated with an 11 % lower polar strength strain index (SSIp) at the radius (p = 0.04) and tibia (p = 0.002) in models adjusted for A1C levels. In women, each additional 1 % increase in A1C was associated with an 18 % lower SSIp at the ultradistal radius (p = 0.04) in models adjusted for TZD use. There was no consistent evidence of an effect of intensive, compared with standard, glycemic control on bone strength at the radius or tibia. In women, TZD use may reduce bone strength at these sites. Higher A1C may also be associated with lower bone strength at the radius, but not tibia, in women. 相似文献