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71.
Wells JP  Beckett H 《Dental update》2008,35(4):253-256
A focused literature search to appraise the safety and suitability of articaine as a substitute for lignocaine was conducted. An evidence-based approach to the current available literature suggests that articaine is an effective and well-tolerated anaesthetic for dental use. However, practitioners should be aware of a possible, as yet unproven, link between 4% concentrations of local anaesthetic solution and nerve damage. Clinical Relevance: The purpose of this paper is to share the findings of our focused literature review with general dental practitioners and outline the available evidence on the safety and use of articaine as a substitute for lignocaine.  相似文献   
72.
Abstract: This study investigated the change over time in the area of the posterior mandibular residual ridge in patients wearing either i) mandibular overdentures stabilised by two implants (Brånemark System; Nobel Biocare, Göteborg, Sweden) connected by a bar, or ii) mandibular fixed cantilever prostheses stabilised on five or six implants. Proportional measurements were made in order to compare the area of the residual ridge with an area of bone uninfluenced by resorption. Measurements were made by digitising tracings of panoramic radiographs that were taken shortly after implant insertion and up to seven years later. With the use of overdentures, the posterior bone area index reduced by a mean of 1.1% per annum, while a mean bone area index increase of 1.6% per annum was demonstrated in association with fixed prostheses. A multiple linear regression model was fitted to predict the change in posterior area from type of prosthesis, gender, age, years of edentulism and initial height of the mandible. The model was only significant for initial height of mandible (P = 0.04) and type of prosthesis (P = 0.0001). In conclusion, patients rehabilitated with implant‐stabilised mandibular overdentures demonstrated low rates of posterior mandibular residual ridge resorption, while patients rehabilitated with implant‐stabilised mandibular fixed cantilever prostheses demonstrated bone apposition in the same area.  相似文献   
73.
74.
STATEMENT OF PROBLEM: Die stones require abrasion resistance, dimensional stability with time, and high surface wettability material properties. PURPOSE: The purpose of this study was to compare the surface microhardness (Knoop) of 4 contemporary gypsum materials with and without surface die hardener. MATERIAL AND METHODS: Materials used were a Type III stone (Microstone) and 3 die stones (Die-Keen, Silky-Rock, and ResinRock). Die hardener was cyanoacrylate (Permabond 910) or Clear Coat. Specimens of stone were hand mixed with distilled room temperature water and vacuum spatulated according to manufacturer's directions. Five cylinders (15 x 15 mm) per group were poured, using vibration, into phenolic ring molds positioned on top of a glass slide. The face of each specimen was polished with 2400-grit Al2O sandpaper. One face of each of 5 specimens/material was coated with cyanoacrylate; 5 specimens/material were coated with Clear Coat, air thinned and dried; and 5 specimens/material had no treatment (control). Knoop hardness (kg/mm2) readings were made on each face (5 readings/time point) 3, 12, and 24 hours after pouring. An ANOVA procedure with post hoc Tukey tests were performed (alpha=.05). RESULTS: Microhardness did not vary between 3 and 24 hours for any material (P>.05). Microstone had significantly lower surface hardness (P<.0001) than the die stones. Specimens coated with die hardener had lower hardness values (P<.001 in all cases) CONCLUSIONS: The 3 types of die stones evaluated in this study did not differ significantly in surface microhardness. Under these conditions, die hardener coatings reduced the surface hardness of the gypsum material.  相似文献   
75.
Electrocautery can induce significant alterations in the connective tissues and epithelium of specimens removed for diagnostic or therapeutic purposes. When electrocautery is used during parotid surgery, it can cause an oncocytoid artifact. The alterations described in this article are enlarged, tightly packed serous acinar cells with coarse to granular eosinophilic cytoplasm, distinct cell borders, and round basal nuclei that on cursory microscopic examination resemble oncocytes with respect to morphology. These changes are seen in conjunction with other, more recognized changes secondary to electrocautery and are believed to occur as a consequence of the electrothermal discharge. On the basis of our findings, this artifact is common in parotid surgical specimens and was misdiagnosed as benign oncocytic lesions in 5 cases.  相似文献   
76.
Oral candidal infection is a common problem in bone marrow transplantation. This prospective study compared the effectiveness of antifungal prophylaxis with topical antifungals (nystatin and amphotericin B suspensions) versus oral fluconazole in 196 patients undergoing bone marrow transplantation. Oral candidosis occurred frequently in the group receiving topical antifungals (61/113, 54%), but was rare in the group receiving fluconazole (6/83, 7%). The difference in efficacy between the two groups was highly significant (p<0.00001). There was no difference in the incidence of suspected systemic fungal infection between the two groups. While nausea was a problem with antifungal suspensions, no significant adverse reactions to fluconazole occurred. Because of greater efficacy in preventing oral candidosis and better patient tolerance, oral fluconazole is preferred to antifungal suspensions for prophylactic use in patients undergoing bone marrow transplantation.  相似文献   
77.
The purpose of this study was to examine the clinical and microbiological effects of localized ligature-induced periodontitis on non-ligated sites in a monkey model system. Ligature-induced periodontitis was produced in one quadrant in each of four Macaca fascicularis monkeys. Two additional monkeys without any ligatures served as control. The clinical condition and subgingival microflora of ligated, non-ligated, and control sites were monitored for 8–11 weeks. Ligated sites demonstrated an initial (1–2 weeks post-ligation) increase in inflammation, Gram-negative surface translocating bacteria (STB), and motile rods. Clinical and radiographic evidence of loss of attachment associated with increased proportions of Bacteroides gingivalis was evident 4–6 weeks post-ligation. No clinical changes were demonstrated in non-ligated and control sites throughout the experimental period. Non-ligated sites, however, demonstrated an increase from 4.6% to 13.7% in Gram-negative STB and motile rods by 4–6 weeks which continued to increase to 20.3%, by 8–11 weeks. Control sites showed no microbiological changes during the experimental period. In a second experiment pure cultures of B. gingivalis were implanted subgingivally at various times in non-ligated sites. It was only possible to recover increased proportions of B. gingivalis from non-ligated sites when implantation occurred while proportions of Gram-negative STB and motile rods were elevated. Loss of attachment in infected non-ligated sites was not seen within four weeks of implantation.  相似文献   
78.
Preventive Behaviors as Correlates of Periodontal Health Status   总被引:1,自引:0,他引:1  
Objectives: This investigation examined current practices of brushing, flossing, and periodic dental visits and their association with periodontal health status. Methods : Data were collected using face-to-face interviews and 40-minute in-home dental examinations with a probability sample of adults 18 years of age or older, having at least one tooth, and living in housing units in the Detroit tricounty area. Complete examinations were performed on 319 individuals. Results : On average, subjects reported brushing their teeth about twice a day. About one-third of the population reported flossing at least once a day. Loss of periodontal attachment was related to frequency of brushing while subjects who exhibited acceptable flossing ability had less plaque and calculus, shallower pocket depths, and less attachment loss. Subjects reporting a periodic dental visit at least once a year had less plaque, gingivitis, and calculus than subjects reporting less frequent visits. In regression analyses, brushing thoroughness, flossing ability and frequency, and dental visit frequency were predictors of lower plaque, gingivitis, and calculus scores. In turn, these scores were predictors of shallower pocket depths and less attachment loss. Conclusions : Brushing, flossing, and periodic dental visits were correlated with better periodontal health. The behaviors appeared to be indirectly related to pocket depth and attachment loss through their associations with plaque, gingivitis, and calculus levels.  相似文献   
79.
Constant proportions in mixing of alginate impression material are difficult to achieve, especially in a teaching department, owing to variability in powder measurement with the conventional scoop method. Apparatus to facilitate powder measurement by weighing is described, and its accuracy assessed.  相似文献   
80.
A double-blind randomized clinical trial of the effectiveness of orally administered diazepam in reducing dental anxiety was conducted. Forty-one subjects were assigned to a diazepam or placebo group and tested, using the Dental Fear Survey and State-Trait Anxiety Inventory. Diazepam was effective in reducing anxiety scores but not dental fear scores.  相似文献   
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