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61.
62.
Among leukemia patients, a significant number of deaths are due to Candida septicemia, many of which are associated with previous oral infections. Oral candidiasis detection methods vary, and the relationship between oral candidiasis and Candida colonization (CC) is not well defined. The main objectives of this study were to compare the incidence of CC in a healthy and leukemic population, and also to evaluate the efficacy of three simple and inexpensive methods of detecting oral CC in predicting the occurrence of oral candidiasis. A secondary objective was to portray speciation in the examined populations. Forty-two pediatric leukemia patients and 42 healthy, age-, race-, and gender-matched control patients participated in this study. The three methods of detection were cytological examination of the oral mucosa, and direct culture methods from mucosal smears using Sabouraud's dextrose agar (Becton Dickinson Microbiology Systems, Cockeysville, MD) and Oricult-N (Orion Diagnostica, Espoo, Finland). This study demonstrated an increased prevalence of CC in pediatric leukemia patients with the direct culture method detecting CC in a significantly greater proportion of the population (Oricult-N,P = 0.034; Sabouraud's dextrose agar, P = 0.0036). Candida albicans was the predominant species. Further study is needed to determine the clinical significance of oral CC and its relationship to oral candidiasis and systemic infection in pediatric leukemia patients. 相似文献
63.
64.
Brown LJ Wagner KS Mikkelsen MC Munson B 《Journal of the American Dental Association (1939)》2005,136(6):797-804
BACKGROUND: The American Dental Association conducts surveys of educational programs in dental assisting, dental hygiene and dental laboratory technology. The 2002-2003 survey included questions about enrollment, graduates, program information and trends. METHODS: The ADA Survey Center mailed the Survey of Allied Dental Education to 548 program directors of dental assisting, dental hygiene and dental laboratory technology educational programs. They also sent several follow-up notices as a reminder to complete the survey. A 100 percent response rate is mandatory for continued accreditation by the Commission on Dental Accreditation. Association staff members resolved inconsistencies in the data and analyzed them before producing a final report. RESULTS: The number of applications to, first-year enrollment in and number of graduates in dental hygiene and dental assisting educational programs have increased during the last five years. During the same period, the number of applications to, and graduates of, dental laboratory technology educational programs decreased, but first-year enrollment increased slightly. CONCLUSIONS: Results from these surveys help address the concerns of the public and the profession regarding allied dental manpower levels. They also provide information for those interested in applying to individual allied dental educational programs. PRACTICE IMPLICATIONS: Private dental practices employ the majority of graduates of allied dental educational programs. Recent graduates of dental assisting and hygiene programs continue to supply the office staff members needed to support the delivery of dental care. 相似文献
65.
Surface characterization of retrieved NiTi orthodontic archwires 总被引:9,自引:0,他引:9
The structure and morphological condition of retrieved NiTi orthodontic archwires was evaluated and any possible alterations in the surface composition of the alloy following 1-6 months in vivo were characterized. NiTi wires (GAC, German Orthodontics, ORMCO) of various cross-sections were collected through a retrieval protocol and were subjected to multi-technique characterization. Optical microscopy revealed islands of amorphous precipitants and accumulated microcrystalline particles. Micro MIR-FTIR investigation of the retrieved samples demonstrated the presence of a proteinaceous biofilm, the organic constituents of which were mainly amide, alcohol, and carbonate. Scanning electron microscope and X-ray microanalysis showed that the elemental species precipitated on the material surface were Na, K, Cl, Ca, and P, forming NaCl, KCl, and Ca-P precipitates. Increased intra-oral exposure was consistently associated with the presence of a mature film, while evidence of alloy delamination, pitting, and crevice corrosion, as well as a notable reduction in the alloy grain size was observed. Intra-oral exposure of NiTi wires alters the topography and structure of the alloy surface through surface attack in the form of pitting or crevice corrosion or formation of integuments. Further in vivo research is required to resolve the implications of the described ageing pattern in the corrosion resistance of the alloy, the potential for nickel leaching, as well as bracket-archwire friction variants. 相似文献
66.
Bone augmentation techniques 总被引:2,自引:0,他引:2
BACKGROUND: The advent of osseointegration and advances in biomaterials and techniques have contributed to increased application of dental implants in the restoration of partial and completely edentulous patients. Often, in these patients, soft and hard tissue defects result from a variety of causes, such as infection, trauma, and tooth loss. These create an anatomically less favorable foundation for ideal implant placement. For prosthetic-driven dental implant therapy, reconstruction of the alveolar bone through a variety of regenerative surgical procedures has become predictable; it may be necessary prior to implant placement or simultaneously at the time of implant surgery to provide a restoration with a good long-term prognosis. Regenerative procedures are used for socket preservation, sinus augmentation, and horizontal and vertical ridge augmentation. METHODS: A broad overview of the published findings in the English literature related to various bone augmentation techniques is outlined. A comprehensive computer-based search was performed using various databases that include Medline and PubMed. A total of 267 papers were considered, with non-peer-reviewed articles eliminated as much as possible. RESULTS: The techniques for reconstruction of bony defects that are reviewed in this paper include the use of particulate bone grafts and bone graft substitutes, barrier membranes for guided bone regeneration, autogenous and allogenic block grafts, and the application of distraction osteogenesis. CONCLUSIONS: Many different techniques exist for effective bone augmentation. The approach is largely dependent on the extent of the defect and specific procedures to be performed for the implant reconstruction. It is most appropriate to use an evidenced-based approach when a treatment plan is being developed for bone augmentation cases. 相似文献
67.
Martin Steiner DDS Professor Alan R Gould DDS MSc Professor George M Kushner DMD MD Assistant Professor Bradley Lutchka DMD MD Robert Flint DMD MD 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》1997,84(6):703-707
Myositis ossificans traumatica of the masseter muscle is uncommon. The condition is benign and results in reactive heterotopic bone formation, usually producing limitation of opening of the jaws. Radiographic and microscopic examination can confirm the diagnosis. Treatment of myositis ossificans traumatica of the masseter muscle is surgical, with other modalities used when occurring in other muscles of the body 相似文献
68.
Purpose
The purpose of this study was to determine whether treatment outcomes vary according to the design of the mandibular repositioning appliance (MRA). Two titratable MRA's were compared. The designs differ in advancement hardware and configuration of acrylic both in bulk and interocclusal contact.Materials and methods
The primary treatment outcome was the Respiratory Disturbance Index (RDI). Other outcomes that were compared included Sleep Apnea Quality of Life Index (SAQLI), Epworth Sleepiness Scale, oxygen saturation, and subjective feedback regarding experiences with the appliances. Twenty-four subjects were recruited from consecutive referrals for MRA therapy following diagnosis of obstructive sleep apnea (OSA) by polysomnography. Subjects were randomly assigned to a treatment arm of the crossover study. Each subject underwent an initial sleep study with a type III home monitor to establish a baseline RDI. Subjects were then treated with one of the two MRAs determined by random assignment. The MRA self-titration phase was monitored until a treatment position was determined, and the home sleep study was repeated. After a 2-week period without any OSA treatment, subjects received the second MRA and the self-titration treatment protocol was repeated. At completion of treatment with each appliance, subjects answered questionnaires and underwent a sleep study with the type III monitor. The outcome data for each appliance were compared using analysis of variance.Results
Eighteen subjects completed the treatment protocol. There were no significant statistical differences in treatment outcomes between the two appliances. There was a statistically significant (p?≤?0.05) preference for a MRA design with minimal coverage of teeth and palate. The subjects' appliance selection was consistent with a corresponding reduction in SAQLI score for the selected appliance.Conclusion
Although no statistically significant difference was observed between the two appliances in the outcomes measured, there was a trend toward greater improvement with the appliance with less acrylic resin bulk and less interocclusal contact. MRA selection should favor titratable, unobtrusive designs with appropriate construction to promote acceptance and adherence to MRA therapy. 相似文献69.
Bradley D. Allen Michael Markl Alex J. Barker Pim van Ooij James C. Carr S. Chris Malaisrie Patrick McCarthy Robert O. Bonow Preeti Kansal 《The international journal of cardiovascular imaging》2016,32(4):621-628
In patients with bicuspid aortic valve (BAV), beta-blockers (BB) are assumed to slow ascending aorta (AAo) dilation by reducing wall shear stress (WSS) on the aneurysmal segment. The aim of this study was to assess differences in AAo peak velocity and WSS in BAV patients with and without BB therapy. BAV patients receiving BB (BB+, n = 30, age: 47 ± 11 years) or not on BB (BB?, n = 30, age: 46 ± 13 years) and healthy controls (n = 15, age: 43 ± 11 years) underwent 4D flow MRI for the assessment of in vivo aortic 3D blood flow. Peak systolic velocities and 3D WSS were calculated at the anterior and posterior walls of the AAo. Both patient groups had higher maximum and mean WSS relative to the control group (p = 0.001 to p = 0.04). WSS was not reduced in the BB+ group compared to BB? patients in the anterior AAo (maximum: 1.49 ± 0.47 vs. 1.38 ± 0.49 N/m2, p = 0.99, mean: 0.76 ± 0.2 vs. 0.74 ± 0.18 N/m2, p = 1.00) or posterior AAo (maximum: 1.45 ± 0.42 vs. 1.39 ± 0.58 N/m2, p = 1.00; mean: 0.65 ± 0.16 vs. 0.63 ± 0.16 N/m2, p = 1.00). AAo peak velocity was elevated in patients compared to controls (p < 0.01) but similar for BB+ and BB? groups (p = 0.42). Linear models identified significant relationships between aortic stenosis severity and increased maximum WSS (β = 0.186, p = 0.007) and between diameter at the sinus of Valsalva and reduced mean WSS (β = ?0.151, p = 0.045). Peak velocity and systolic WSS were similar for BAV patients irrespective of BB therapy. Further prospective studies are needed to investigate the impact of dosage and duration of BB therapy on aortic hemodynamics and development of aortopathy. 相似文献
70.
L Esperanza D A Holt J T Sinnott M R Cancio E A Bradley M Deutsch 《Southern medical journal》1992,85(7):754-755
An occasional patient presents the classical symptoms of a disease that has become uncommon. Typhus is an example of such a disease, since it is now well contained through control of its rodent reservoir. It is readily treated with tetracycline or one of its long-acting analogues, doxycycline or minocycline. Because typhus is infrequently encountered, the physician may not initially include it in his differential diagnosis. Our case serves as a remainder that with the increasingly frequent movement of persons from one geographic area to another, the uncommon rickettsial infection, murine typhus, should continue to be in the differential of a febrile patient. Furthermore, our case underscores the importance of including typhus in the differential of typhoid fever. 相似文献