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951.
In 1997, the American Dental Association (ADA) and the American Academy of Orthopaedic Surgeons (AAOS) published an advisory statement regarding antibiotic prophylaxis for patients with total joint replacements undergoing dental treatment. The first periodic update of these guidelines was published in 2003. Nevertheless, confusion exists among dentists and physicians as to the clinical indications for premedication in this patient population. This article serves as an overview of current recommendations for use of chemoprophylaxis in the dental treatment of patients ith prosthetic joints.  相似文献   
952.
This study evaluated the fracture loads of three-unit all-ceramic bridges on implants; the core frameworks of the bridges were made of zirconium oxide. Three core framework designs were fabricated according to the design of the bars between the retainers: (i) straight, (ii) curved in the occlusal direction, or (iii) curved in the gingival direction. A static load was applied at the centre of the pontic, and the mean initial crack and final fracture loads were measured and compared. The core framework curved in the occlusal direction had the highest final fracture loads; there were significant differences (P < 0.05) in the mean final fracture load, whereas initial fracture load, which fractured of veneered porcelain, did not show significant differences among three designs. The all-ceramic bridges on the implants made with Procera zirconium core frameworks had high final fracture load. The core framework design that curved in the occlusal direction helped the framework withstand the occlusal load, which results in reliable prostheses, especially in the molar region.  相似文献   
953.
Nuclear factor kappaB p65 phosphorylation in orthodontic tooth movement   总被引:1,自引:0,他引:1  
Osteoclasts play a vital role in orthodontic tooth movement. Transactivation of nuclear factor kappaB (NFkappaB) by phosphorylation of the p65 component of NFkappaB at amino acid 536 (p65*(536)) plays a role in osteoclast differentiation stimulated by receptor activator of nuclear factor kappaB-ligand (RANK-L). We hypothesized that this transactivation pathway might be involved in the responses of alveolar bone cells during orthodontic tooth movement. We detected sharp increases in the levels of p65*(536) 3 and 12 hrs after the application of orthodontic stimuli in rats. In cell culture, osteoclast-like cells displayed no changes in p65*(536) in response to RANK-L, but levels rapidly increased after the cells were mechanically scraped. We conclude that p65*(536) is produced rapidly in response to orthodontic stimuli and mechanical insults, and may be important in bone remodeling associated with orthodontic tooth movement.  相似文献   
954.
Although arthrocentesis is not a panacea, it has been widely used for a variety of temporomandibular joint (TMJ) disorders. Uncritical acceptance of the procedure has been cautioned against, as further analysis and clarification of published studies was required. The aim of this article was to review the efficacy of arthrocentesis in the treatment of patients with TMJ closed lock. The rationale behind this approach was based on the notion that TMJ surgical results should be reported by the specific category of TMJ disorder. After a Medline search of the international literature, 14 articles were found fulfilling the criteria set forth by this article. Another five articles were added after an additional hand search based on the available references of the papers found. The majority of the reviewed publications were prospective case series with flawed methodology and, despite the impression that arthrocentesis may be beneficial for patients with TMJ closed lock, there have been no good prospective randomized clinical trials that confirm the efficacy of this procedure.  相似文献   
955.
Endoscopy is widely used in the diagnosis and treatment of temporomandibular joint disorders. This paper introduces arthro-endoscopy as a new method of treatment for temporomandibular joint dislocation. As this method is minimally invasive, it is suitable for medically compromised patients who cannot tolerate open surgery.  相似文献   
956.
Resection is the preferred treatment for oral squamous cell carcinoma, and pathological staging of the resected specimen is crucial. The role of molecular biology in the diagnosis of minimal residual disease has not been fully investigated and may improve staging. Multiple adjacent specimens were taken from the tumour, the invasive front, the surgical margin, and the lymph nodes of 20 specimens from patients with oral cancer. Bisulphite-treated DNA from these specimens was assayed quantitatively with pyrosequencing methylation assays (PMA) of CpG islands within the gene promoters of the p16 and CYGB genes. Results were recorded with histopathological results, and compared with clinical outcome. Biological and technical replicates confirmed the reliability of the techniques. PMA upgraded 13 of the 20 surgical margins, 6 of which subsequently had a recurrent tumour. Not all of these recurrences were predicted and the effects of adjuvant treatment make firm conclusions difficult.  相似文献   
957.
AIM: To compare the remineralisation effects of different child dentifrices on primary teeth. DESIGN: In vitro single-section technique and pH-cycling model. METHODS: Primary teeth were painted with nail varnish, leaving a 1 mm wide window before placing in demineralising solution for 96hr to produce artificial carious lesions 150-200 microm deep. Teeth were longitudinally cut into approximately 100-150 microm thick sections and assigned to three groups (n = 7). Sections in Group A were exposed to Perioe Children's Toothpaste (LG, Korea), Group B to Colgate Pokemon (Colgate-Palmolive, Thailand) and Group C to Vicco (Vicco Laboratories, India). Polarised light microscopy and microradiography was used to evaluate lesion depth, before and after 7 days pH cycle. RESULTS: Mean lesion depths in Groups A and C increased by 11% and 14% respectively, while Group B demonstrated a lesion reduction of 3%. Comparisons using ANOVA and Student-Newman-Keuls tests showed that Groups A and C were significantly different from Group B (p < 0.05), but there was no significant difference between Groups A and C. CONCLUSIONS: Based on the data obtained, Colgate Pokemon remineralised initial carious lesions. In addition, when compared to Colgate Pokemon, Perioe Children's Toothpaste failed to show 'healing' efficacy even though it is claimed to contain fluoride.  相似文献   
958.
959.
The National Board Dental Hygiene Examination program is a part of the process for licensing dental hygienists. The examination assesses theoretical and applied knowledge in the basic biomedical, dental, and dental hygiene sciences, as well as community health. Standards for licensure examinations recommend that test publishers demonstrate a relationship between examination content and actual practice. METHOD: To this end, a validity study was conducted, which involved the definition of the domain of entry-level dental hygiene practice using 56 competencies; the conduct of a practice analysis survey designed to rate the importance of these competencies; and the linking of competencies to content elements in accordance with the competencies' importance ratings. Of the 3941 surveys distributed, 1841 participants responded and, of these, 1284 were full-time practitioners. The importance ratings for the competencies were translated into numbers of items. The number of items devoted to each competency was distributed across all applicable elements of the existing content specifications based upon the knowledge needed to support the realization of the competency. RESULTS AND DISCUSSION: The findings confirmed the adequacy of the content specifications in effect prior to 2005. However, based on this validity study, 2 sub areas of relatively little significance were eliminated, and 2 new areas were introduced. Specifically, Clinical Testing under Assessing Patient Characteristics (one item) and Professional Methods of Administering Fluorides under Using Preventive Agents (one item) were eliminated, and Dental Hygiene Treatment Strategies was incorporated with 4 items, and Professional Responsibilities was added with a total of 28 items.  相似文献   
960.
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