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This study found that dental treatment with 2% lidocaine with 1:100,000 epinephrine did not provoke myocardial ischemia, as assessed by greater than or equal to 1 mm of ST segment depression. Although in some cases systolic and diastolic blood pressure and rate pressure product increased slightly after local anesthetic administration, these changes were not statistically significant. Because these patients were medically supervised and compliant with cardiac therapy, this study suggests that such patients are not at great risk while receiving local anesthesia with 1:100,000 epinephrine for routine dental care.  相似文献   
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BACKGROUND: Codeine is frequently added to paracetamol to treat post-operative dento-alveolar pain; studies have shown effectiveness in relief of post-operative pain at high doses but at the expense of central nervous and gastrointestinal side effects. There has been no trial to compare the efficacy and safety of paracetamol 1000 mg with paracetamol 1000 mg combined with codeine 30 mg. METHOD: A randomized, single centre, double-blind prospective parallel group trial was performed to compare paracetamol 1000 mg with paracetamol 1000 mg with codeine 30 mg for the relief of pain following surgical removal of impacted third molars, and analysed on an intention-to-treat (ITT) basis. Eighty-two patients were assigned randomly to receive either drug for a maximum of three doses. Patients recorded their pain intensity one hour after surgery and hourly thereafter for 12 hours. RESULTS: The average increase in pain intensity over 12 hours was significantly less in patients receiving paracetamol plus codeine than in those receiving paracetamol alone (p=0.03) -1.81 cm/h compared with 0.45 cm/h - a difference of 1.13 cm/h (95 per cent CI: 0.18 to 2.08). Of the patients who received the paracetamol codeine combination, 62 per cent used escape medication compared with 75 per cent of those on paracetamol alone (p=0.20). There was no significant difference between the two groups in the proportion of patients experiencing adverse events (p=0.5). CONCLUSION: A combination of 1000 mg paracetamol and 30 mg codeine was significantly more effective in controlling pain for 12 hours following third molar removal, with no significant difference of side effects during the 12 hour period studied.  相似文献   
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Since the introduction of necrotizing sialometaplasia into the literature as a distinct pathologic entity in 1975, there have been several reports containing microscopic findings consistent with the disease primarily of the hard palate, but also of the soft palate, major salivary glands, retromolar pad of the mandible, and mucous glands of the nasal cavity. Localized ischemia appears to be a common link. All reported lesions heal with or without surgical intervention. Generous incisional biopsy specimens should be taken and aggressive surgery should be avoided.  相似文献   
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PURPOSE: This research determined whether there is a measurable effect of local geometry factors on leucite content of dental porcelain in fixed partial dentures (FPD). MATERIALS AND METHODS: Four-unit FPD frameworks (n = 36) were fabricated using a nickel-chromium alloy (Rexillium III). Body porcelain (Crystar, shade A2) was applied in one increment and subjected to two simulated body firings, followed by a simulated glaze firing to achieve a thickness of 1.5 to 2.0 mm. The completed FPD specimens were randomly assigned to three groups of 12 specimens each: (1) simulated post-soldering, (2) multiple firing, and (3) control. The FPDs from each test group were sectioned into individual units: canine retainer, premolar pontic, molar pontic, and molar retainer. The porcelain was removed from each unit, and the leucite content was measured via quantitative x-ray diffraction. RESULTS: Porcelain cracking indicated that the soldering simulation had successfully reproduced conditions in the dental laboratory that result in porcelain cracking during soldering. The leucite content was not significantly different between the retainer and pontic units for either the soldering simulation or control FPDs, although the canine retainer units did have a slightly lower leucite content than the pooled values of the other units. Comparison of the pooled data for the three groups indicated statistically significant differences among the leucite contents. CONCLUSION: Compared to the control, the simulated post-soldering procedure produced a significant increase in leucite, and the multiple firing group exhibited a significant decrease in leucite. Increases in leucite weight fraction during post-soldering operations-and the larger thermally induced stresses that accompany these leucite increases-are responsible for the cracking that occurs.  相似文献   
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Parental smoking practices and caries experience in pre-school children   总被引:1,自引:0,他引:1  
Voluntary and involuntary smoking influence general health. Links between voluntary smoking and oral health are confirmed for periodontal diseases and oral cancer/precancer. Since recent reports have suggested an association between parental smoking and caries experience in young children, this study aimed to explore varying patterns of parental smoking, adjusted for social class, with caries prevalence, using data derived from the UK National Diet and Nutrition Survey (1995). Data analysis was confined to 749 children aged 3.0-4.5 years, to avoid confounding effects of unerupted teeth. Bivariate analysis indicated that the prevalence of maternal rather than paternal smoking was significantly related to caries and substantially attenuated social class differences. The reported number of cigarettes smoked was not important. To compensate for the association between social class and maternal smoking, data were dichotomised by social class (manual/non-manual). With caries prevalence as the dependent variable, logistic regression analysis recorded maternal smoking as a significant independent variable in each case, with odds ratios of 1.55/1.96, respectively. The process was repeated for the combined dataset, using the more extensive (six) social class categories. This further analysis yielded an odds ratio for maternal smoking of 1.54 compared with 1.46 for social class. Nutrition status (as growth parameters) and dietary intake (as household spending on confectionery) were not significant independent variables in these equations. The rationale for these findings is discussed. Further research is required to determine mechanisms underlying these observations. It is concluded that maternal smoking is a significant factor to be considered as an additional risk indicator beyond social class when predicting caries risk in young children.  相似文献   
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