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PURPOSE: This article describes how the concept of platform switching has been incorporated into a new implant design as a method of reducing crestal bone loss and maintaining the gingival papillae. A 6-month study of the effects of this implant on bone loss is described. MATERIALS: Ten new platform switched implants were placed into fresh anterior maxillary extraction sites in 3 men and 7 women, ranging in age between 29 and 45 years old, and immediately provisionalized. The adjoining bone height was evaluated with digital radiography on the day after implant placement, and at 15 days, 1, 2, 3, and 6 months later. RESULTS: After 6 months, the mean bone loss on the mesial of the central-incisor implants was 0.05 mm. The mean bone loss was 0.07 mm on the distal of the central incisor implants, 0.07 mm on the mesial of the lateral-incisor implants, and 0.06 mm on the distal of the lateral-incisor implants. CONCLUSIONS: An implant design that incorporates the concept of platform switching is a simple and effective way to control circumferential bone loss around dental implants, helping to ensure a predictable esthetic result.  相似文献   
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BackgroundThe Robert Wood Johnson Foundation, Princeton, N.J., the W.K. Kellogg Foundation, Battle Creek, Mich., and The California Endowment, Los Angeles, collaborated in funding a five-year (2002–2007) national demonstration program (Pipeline, Profession & Practice: Community-Based Dental Education [Dental Pipeline]) to reduce dental care access disparities. Fifteen dental schools were selected to participate in the Dental Pipeline program. The goals were to have senior students spend more time in community sites providing care to underserved patients; to prepare students to treat diverse, low-income patients; and to increase enrollment of underrepresented minority (URM) students.MethodsA national program office at Columbia University in New York City administered the Dental Pipeline program. The participating dental schools developed networks of community clinics and practices for student rotations, established courses in cultural competency and public health and implemented new programs to recruit URM students.ResultsThe average time senior students spent in community clinics and practices increased from 10 to 50 days; all schools developed courses in cultural competency and public health; and enrollment of UMR students increased 54.4 percent (excluding two of the schools) versus 16 percent in non–Dental Pipeline schools.ConclusionsOn average, the participating dental schools were successful in meeting program goals.  相似文献   
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The normal meniscus undergoes typical developmental changes during childhood, reaching a mature adult appearance by approximately 10 years of age. In addition to recognizing normal meniscal appearances in children, identifying abnormalities — such as tears and the different types of discoid meniscus and meniscal cysts, as well as the surgical implications of these abnormalities — is vital in pediatric imaging. The reported incidence of meniscal tears in adolescents and young adults has increased because of increased sports participation and more widespread use of MRI. This review discusses the normal appearance of the pediatric meniscus, meniscal abnormalities, associated injuries, and prognostic indicators for repair.  相似文献   
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Aim : To investigate whether infants with intrauterine growth retardation (IUGR) experience different changes in temperature and cortisol excretion after routine immunization compared with normal healthy infants. Methods : Overnight deep body temperature and urinary cortisol to creatinine ratios were measured on the night after immunization and a control night in normal and IUGR infants. Results : In 60 normal infants, first vaccination at about 10 wk of age led to a significant increase in minumum overnight temperature compared to the control night, mean rise 0.25°C (95% CI, 0.12 to 0.38). In 35 IUGR infants the mean rise in temperature between immunization night and control night was 0.35°C (95% CI, 0.15 to 0.55). The increases in minimum temperature did not differ significantly between the normal and IUGR infants ( p = 0.11). Cortisol to creatinine ratios measured from overnight urine samples showed that 23 IUGR infants had consistently higher levels than 39 normal infants; control night medians 34 and 15 ( p = 0.01) and immunization night medians 56 and 26 ( p= 0.02), respectively. However, the percentage increase did not differ significantly between the IUGR infants and the normal infants. A smaller number of second immunizations were studied, but no significant differences were found.

Conclusion : These results suggest that although the impact of immunization is the same for IUGR and normal infants, because IUGR infants are less mature and at greater stress before immunization, the absolute levels that they experience after immunization are higher than those for normal infants.  相似文献   
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