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1.
BACKGROUND: White spot lesions are observed in nearly 50% of patients undergoing orthodontic treatment. Long-lasting antibacterial properties of orthodontic cements can reduce this phenomenon. METHODS: The antibacterial properties of 4 orthodontic cements were evaluated by direct contact test (DCT) and agar diffusion test (ADT). With the DCT technique, octet specimens of glass ionomer (CX-Plus; Shofu, Kyoto, Japan), reinforced glass ionomer (GC Fuji ORTHO LC; GC Corporation, Tokyo, Japan), and 2 composite (Transbond XT and Transbond Plus; 3M Unitek, Monrovia, Calif) orthodontic cements were placed on the sidewalls of wells of a 96-microtiter plate. Streptococcus mutans cells (ca. 1 x 10(6) ) were placed on the surface of each specimen for 1 hour at 37 degrees C. Then, fresh media was added to each well, and bacterial growth was monitored for 16 hours with a temperature-controlled spectrophotometer. This was repeated on specimens aged in phosphate-buffered saline for 1 day, 1 week, and 1 month. The ADT was performed by placing specimens in wells punched in agar plates. RESULTS: Measurement of the halo in bacterial lawn after 48 hours showed that only the glass ionomer cement (CX-Plus) produced an inhibition zone (1.2 mm around the sample). Results at the DCT showed that only the reinforced glass ionomer cement (GC Fuji ORTHO LC) exhibited potent antibacterial activity, which lasted 1 week and diminished over the next 3 weeks. CONCLUSIONS: The reinforced glass ionomer cement possessed the most potent and long-lasting antibacterial activity.  相似文献   
2.
Assessment of carbohydrate tolerance in pregnancy   总被引:4,自引:0,他引:4  
A review is given of the various methods of assessing carbohydrate tolerance in pregnancy. Oral glucose tolerance screening and diagnostic tests have been in use for more than 25 years. They are easily administered, relatively inexpensive, and present reasonable sensitivity; therefore, they continue to be used quite extensively. However, lack of reproducibility of the results and side effects such as nausea, vomiting, and headache have led to the use of alternate methods including glucose polymer (Polycose) and standard breakfast meals. These methods have been reported to present satisfactory results in clinical practice. Glycosylated hemoglobin (HbA1c) and fructosamine assays are also alternate forms of testing carbohydrate metabolism HbA1c measurement have been proven insensitive as a screening test for gestational diabetes, while their use as an index of overall glucose control remains valuable. The role of fructosamine in the assessment of carbohydrate intolerance remains controversial with conflicting claims made by various investigators regarding its sensitivity in detecting gestational diabetes and its response to alterations in glycemic control. In this review, the relative advantages and disadvantages of each glucose tolerance test are discussed and recommendations are given regarding their utility in pregnancy.  相似文献   
3.
Breast carcinoma is the most common type of cancer affecting women in the Western world. The hereditary forms, which amount from 5 to 10% of all the cases of breast cancer, mainly involve BRCA1 or BRCA2 mutations. Due to the diagnostic strategy used by the patent owner, Direct DNA sequencing (DS) may become the only BRCA1/2 test procedure available, although there exist several alternative strategies. A cost-effectiveness study was carried out using BRCA1 testing as a model. The main techniques available for performing mutation searches were assessed: DS, denaturing high performance liquid chromatography (DHPLC), single-strand conformation polymorphism (SSCP), denaturing gradient gel electrophoresis (DGGE), heteroduplex analysis (HA), fluorescent assisted mismatch analysis (FAMA) and the protein truncation test (PTT). Twenty strategies involving the use of one or more techniques were then devised for performing the complete genetic analysis. DS was adopted as the 'gold standard' for effectiveness. All the strategies except for DS involved a two-step procedure. The first step consisted of pre-screening the 22 coding exons of BRCA1. The second step consisted of performing DS only on the variations detected in the coding sequence. The cost of the strategies tested, including a pre-screening stage, turned out to be 30 to 90% lower than that of DS, whatever annual use was made of the equipment. The most cost-effective strategy, ie, that corresponding to the lowest cost per mutation detected, was found to be a combination between PTT on exon 11 (60% of the coding sequence) and HA on the remaining 21 exons (PTT(11)+ HA(21)). However, since a high false negative rate is associated with this strategy, at least four other strategies are worth mentioning: PTT(11)+ DHPLC(21), DHPLC alone, FAMA(11)+ DHPLC(21) and FAMA alone. Our results on genetic testing for breast cancer show that DS is not the most cost-effective method available. The monopolist approach of the firm which owns the patents on the BRCA1/2 genes, may, therefore limit the use of the most cost-effective strategies.  相似文献   
4.
Stereotactic 11-Gauge vacuum-assisted biopsy provides a valuable tool in the diagnosis of mammographically detected breast microcalcifications. However, this new diagnostic technology presents some limitations and requires a close collaboration between radiologists, pathologists and physicians. The aim of this work is to propose a practical approach in the management of large core biopsies and to summarize the different difficulties faced by the pathologist in the management and histological interpretation of specimens issuing from this device.  相似文献   
5.
6.
Acute myocardial infarction during pregnancy is considered to be associated with approximately 50% mortality of both mother and fetus. However, there are not enough data regarding the role of acute myocardial ischemia. We present a 36-year-old, pregnant, white female who was admitted twice at 18 and 20 weeks of gestation with acute myocardial ischemia. Cardiac catheterization revealed 70–80% stenosis of the mid left anterior descending artery (LAD) with normal antegrade flow and very good retrograde filling of the LAD from distal collaterals of the right coronary artery. Therefore, due to angiographic suggestion of protected LAD territory, we recommended medical therapy and scheduled a vaginal delivery that was successfully completed without cardiovascular complications. A stress thallium test performed 6 months later was normal, supporting our clinical judgment. In conclusion, every case of a pregnant woman with coronary insufficiency should be treated according to individual coronary anatomy and blood supply to the territory of the diseased artery, and should not be based on the old data in the literature. The decision for revascularization prior to delivery versus medical therapy, or Caesarean section versus natural delivery, should be made by a team of a cardiologist and an obstetrician.  相似文献   
7.

Objective

To describe inpatient complications for primary total knee replacement (TKR) in a period of rapidly growing orthopedic surgery capacity, declining length of stay, and more frequent discharge to rehabilitation facilities.

Methods

Complication incidence according to published coding algorithms was estimated for 35,531 primary TKR admissions of northern Illinois residents to 65 Illinois hospitals. Complication odds were estimated as a function of patients' clinical and sociodemographic status, hospital volume, residency training, TKR length of stay, International Classification of Diseases, Ninth Revision (ICD‐9) coding intensity, and discharges to skilled nursing or rehabilitation facilities.

Results

Primary TKR admissions increased 36% between 1993 and 1999, length of stay declined 43%, average ICD‐9 code use increased 31%, and rehabilitation discharges increased 68%. Major complication rates declined 44% (12.4% to 6.9%; P < 0.0001) over this period, reflecting a 50% reduction in the adjusted odds of complication between 1993 and 1999. There was no association of procedure volume and outcome.

Conclusion

It is likely that the reduction in complications reflects true safety improvements as well as reduced length of stay.
  相似文献   
8.
Clinical Oral Investigations - To assess the potential of ultrasound examination (USE) as an adjunctive method to conventional radiology to evaluate the healing processes occurring after the...  相似文献   
9.
10.

Aim

The technical quality of a root canal treatment is clinically judged by the apical extension and homogeneity of the filling material imaged by periapical radiographs (PA). The aim of this experiment was to evaluate the association between the technical quality of the root canal filling and treatment outcome.

Materials and methods

In 234 teeth (268 roots) that underwent root-canal treatment, the quality of the root canal filling as well as the outcome of the treatment were assessed with both PA and cone-beam computed tomography (CBCT) 2?years after treatment. Satisfactory root filling on PA was defined as 0–2?mm within the radiographic apex without voids; on CBCT scans, the apical end of the canal replaced the radiographic apex. The outcome predictors were analyzed using multivariate logistic regression.

Results

At recall, periapical radiolucent areas were absent in 198 (74%) roots on PA and 164 (61%) roots on CBCT scans. The presence of preoperative periapical radiolucency and the quality of root filling and coronal restoration were identified by both PA and CBCT as outcome predictors (p?<?0.01). Complete absence of post-treatment periapical radiolucency was observed in CBCT scans in 81% and 49% of satisfactory and unsatisfactory root fillings, respectively, as compared to 87% and 61% revealed by PA.

Conclusion

Satisfactory root fillings were associated with a favorable outcome, confirmed by both PA and CBCT.

Clinical relevance

The outcome of root canal treatment is improved once the filling is 0–2?mm from the apex, and no voids could be detected. Technical skills and performance of root canal filling procedures should be emphasized, and suitable methods should be developed in order to achieve more compacted filling materials without voids and at the correct length.  相似文献   
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