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991.
OBJECTIVE: To describe the working practices and level of career satisfaction of dental therapists in New Zealand. DESIGN: Postal survey of dental therapists identified from the New Zealand Dental Council's dental therapy database. One mailing with one follow-up. PARTICIPANTS: Questionnaires were sent to 683 registered dental therapists. Replies were received from 566 (82.9%). OUTCOME MEASURES: Current working practice, career breaks, continuing education, career satisfaction. RESULTS: Respondents had a high career satisfaction, but were much less satisfied with their remuneration. After controlling for age and income satisfaction, therapists who felt that they were valued members of the dental community had over four times the odds of having higher overall job satisfaction. There were no differences in the mean career satisfaction scale score by age, but respondents aged 45 and over had a lower mean income satisfaction scale score than their younger counterparts (p<0.05). Older respondents were more likely to report regularly placing fissure sealants (p<0.05), participating in peer review (p<0.05), and playing a role in team management/coordination (p<0.05) than younger respondents. Most therapists (412; 82.2%) had taken at least one career break, usually for child rearing. A mean of 6.5 years (SD 5.9; range six weeks to 25 years) had been taken in career breaks. Younger therapists were more interested in moving into private practice than their older colleagues (p<0.05). More than half of respondents planned to retire from dental therapy within 10 years. CONCLUSION: Urgent action is required to improve the recruitment and retention of dental therapists in the New Zealand School Dental Service. Measures to reduce the time taken in career breaks could increase the productivity of this workforce. Remuneration and career progression are key issues; therapists need to feel that they are valued members of the dental profession.  相似文献   
992.
This in vivo pilot study was carried out to test the antibacterial effect of glass ionomer containing chlorhexidine (test group) in comparison to conventional glass ionomer (control group). Fifty 6- to 11-year-old children with one occlusal lesion in a molar were randomly allocated to test and control groups in a parallel-group design. The cavity walls and one half of the floor were cleaned and restored with one of the materials without dentine conditioning. The restorations were removed after 7 days. Dentine samples were taken from the cleaned (affected dentine) and noncleaned area (infected dentine) at baseline and at day 7. Samples were anaerobically and aerobically cultivated for mutans streptococci, lactobacilli and total viable bacterial count (TVC) following common laboratory procedures. ANCOVA was used to test for treatment effects. Seven days after treatment, a significant decrease in anaerobic and aerobic bacterial counts (p = 0.0001) was shown. Lower numbers of anaerobic lactobacilli (p = 0.02), TVC (p = 0.008) and aerobic lactobacilli and TVC (p = 0.03), but not of mutans streptococci, were indicated in the test group compared to the control group. A significant reduction in aerobic lactobacilli from infected dentine treated with the glass ionomer containing chlorhexidine (p = 0.05) was observed whereas in affected dentine, anaerobic mutans streptococci, lactobacilli and TVC and aerobic TVC and mutans streptococci were significantly lower in the test group 7 days after treatment (p = 0.01). We conclude that the present pilot study revealed lower microorganism counts in chlorhexidine-containing glass ionomers than in conventional glass ionomers for both affected and infected dentine over a 7-day period.  相似文献   
993.
BACKGROUND: Beta-glucuronidase (betaG) in gingival crevicular fluid (GCF), a marker of neutrophil influx into the crevicular environment, has previously been shown to be correlated with periodontal clinical parameters at individual sites (probing depth and clinical attachment level). Furthermore, elevated levels of betaG were found to be a risk factor for periodontal attachment loss. Analysis of betaG in saliva may be a measure of crevicular neutrophil influx for the whole mouth. The purpose of this cross-sectional study was to evaluate the relationship between betaG activity in saliva and periodontal clinical parameters in subjects demonstrating various levels of periodontal disease. METHODS: The study population consisted of 380 subjects (108 males and 272 females). A sample of unstimulated whole saliva and a venous blood sample were obtained from each subject, and a periodontal examination, which included measurement of probing depth (PD), attachment level (AL), and gingival index (GI) was performed. The unmodified saliva samples were frozen at -20 degrees C and analyzed for betaG activity. The blood samples were analyzed for number of white blood cells, neutrophils, monocytes, lymphocytes, and platelets. Statistical analysis was conducted to determine the association between salivary betaG activity and the whole-mouth clinical periodontal parameters, complete blood count, smoking status, and age. RESULTS: Highly significant correlations between salivary betaG activity and mean probing depth (MPD), mean gingival index (MGI), and the number of sites with probing depth > or = 5 mm were found. When subjects were divided into tertiles based on their MPD and MGI, elevated salivary betaG activity was detected in subjects in the 2 upper tertiles. Logistic regression modeling was used to determine which of the clinical or laboratory parameters were able to identify patients with at least 4 sites with PD > or = 5 mm. Salivary betaG activity > or = 100 produced an odds ratio (OR) of 3.77. In comparison, current and former smokers had an OR of 3.15 and 2.29, respectively. CONLCUSIONS: The results suggest that a significant association exists between periodontal clinical parameters and salivary betaG activity. Due to the non-invasive and simple nature of saliva collection, this association should be studied to determine its usefulness as a screening test for periodontitis, and a means of monitoring the response to treatment.  相似文献   
994.
STATEMENT OF PROBLEM: The strength of all-ceramic restorations can be adversely affected by surface defects, leading to restoration failures. Additionally, when a 2-layer all-ceramic restoration is required for esthetic purposes, part of the stronger ceramic core material is replaced by veneering porcelain. PURPOSE: This study evaluated the effect of different surface treatments on the strength of a ceramic core material and veneering porcelain, as well as the influence of veneering porcelain on the strength of a 2-layer ceramic structure. MATERIAL AND METHODS: Fifty heat-pressed ceramic cores and 30 veneering porcelain discs (17 mm diameter x 2 mm) were made. From the ceramic core group, 20 discs were selected and reduced to a thickness of 1 mm and veneered with 1 mm of porcelain. These specimens were divided into 2 groups of 10 each. The remaining 30 ceramic core and the 30 veneering porcelain discs were divided into 2 sets of 3 equal sized groups (n=10). Ceramic core groups were prepared for testing having the following surfaces: airborne-particle abrasion, ground, and overglazed. Veneering porcelain groups were tested: as fired (no additional treatment), ground, and overglazed. Biaxial flexural strength was measured using the ball-on-ring test method. All specimens were loaded to fracture. One and 2-way analysis of variance were used to analyze the data (alpha=.05). RESULTS: The ceramic core discs were significantly (P=.001) stronger than the veneering porcelain discs for the airborne-particle abrasion, as-fired, and ground surface treatments (82 +/- 11 MPa vs 51 +/- 8 MPa and 93 +/- 14 MPa vs 60 +/- 6 MPa, respectively). For the overglazed treatment, there was not a significant difference between the core (115 +/- 1 4 MPa) and the veneer materials (107 +/- 14 MPa). The ground 1-layer core was significantly (P=.015) stronger (93 +/- 14 MPa) than the 2-layer with the core tested in tension (72 +/- 19 MPa). There was no significant difference between 1-layer veneer overglazed (107 +/- 14 MPa) and 2-layer discs when tested with the veneer in tension (105 +/- 16 MPa). CONCLUSION: The overglazed surface treatment significantly improved the strength of the materials tested, as well as the strength of 2-layer discs with the veneer in tension. The veneering porcelain influenced the strength of 2-layer specimens only when tested with the ground ceramic core surface in tension.  相似文献   
995.
Anti-cardiolipin antibodies in sera from patients with periodontitis   总被引:2,自引:0,他引:2  
Antiphospholipid antibodies are commonly found in patients with systemic lupus erythematosus or the antiphospholipid syndrome, and a subset of such antibodies is associated with prothrombotic events such as stroke and with adverse pregnancy outcomes and fetal loss. We examined sera from 411 patients who were clinically characterized as to their periodontal disease status for serum levels of beta2-glycoprotein I-dependent anti-cardiolipin autoantibodies (anti-CL). The prevalence of patients with chronic periodontitis (CP) and generalized aggressive periodontitis (GAgP) positive for anti-CL (16.2% and 19.3%, respectively) was greater than that in healthy controls (NP) and localized aggressive periodontitis (LAgP) patients (6.8% and 3.2%). Patients with these autoantibodies demonstrated increased pocket depth and attachment loss compared with patients lacking the antibodies. Analysis of the data indicates that patients with generalized periodontitis have elevated levels of autoantibodies reactive with phospholipids. These antibodies could be involved in elevated risk for stroke, atherosclerosis, or pre-term birth in periodontitis patients.  相似文献   
996.
Historically, shade change assessment associated with vital bleaching treatment regimens has been visually evaluated through the use of shade guide tabs. Innovations in the industry of dentistry have brought forth new technologies capable of measuring such changes via the capture and analysis of reflected wavelengths of light. CLINICAL SIGNIFICANCE: This article introduces the use of a 45/0 reflectance spectrophotometer and identifies the advantages and limitations associated with such a technology in the assessment of shade change owing to vital bleaching.  相似文献   
997.
A dentist referred a 35-year-old woman to the department of oral and maxillofacial surgery because of recurrent aphtous-like changes of the oral mucosa and persisting pain. She also experienced similar complaints about her eyes and genitals. This combination of symptoms was suspect for Beh?et's disease.  相似文献   
998.
999.
The epidemiology of HIV-related oral disease in industrialized nations has evolved following the initial manifestations described in 1982. Studies from both the Americas and Europe report a decreased frequency of HIV-related oral manifestations of 10-50% following the introduction of HAART (highly active antiretroviral therapy). Evidence suggests that HAART plays an important role in controlling the occurrence of oral candidosis. The effect of HAART on reducing the incidence of oral lesions, other than oral candidosis, does not appear as significant, possibly as a result of low lesion prevalence in industrialized countries. In contrast to other oral manifestations of HIV, an increased prevalence of oral warts in patients on HAART has been reported from the USA and the UK. HIV-related salivary gland disease may show a trend of rising prevalence in the USA and Europe. The re-emergence of HIV-related oral disease may be indicative of failing therapy. A range of orofacial iatrogenic consequences of HAART has been reported, and it is often difficult to distinguish between true HIV-related oral disease manifestations and the adverse effects of HAART. A possible association between an increased risk of oral squamous cell carcinoma and HIV infection has been suggested by at least three epidemiological studies, with reference to the lip and tongue. These substantial and intensive research efforts directed toward enhancing knowledge regarding the orofacial consequences of HIV infection in the industrialized nations require dissemination in the wider health care environment.  相似文献   
1000.
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