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Background

Fabrication of complete dentures requires the use of certain guidelines which are placed on the bite blocks to assist the clinician to have the maxillary anterior teeth restored to optimal dento-labial relations, in harmony with the overall facial appearance.

Objective

To explore if any relationship exists between dental and facial proportions as well as the height of the individuals.

Methods

Two hundred and four dental students of the Obafemi Awolowo University volunteered to participated in the study. The lower facial height, inter incisal, inter canine, and intercommisure distances, as well as the height of the participants were measured. The data were imputed, analyzed, and reported as simple frequency, means and standard deviations using the SPSS vs 11. Statistical significance was inferred at p<0.05.

Result

The mean values of all the parameters measured were significantly higher in males than females. None of the mean values measured were coincident. However, a significant correlation exists between intercanine and interincisal distances(r=0.8) while a weak but significant negative correlation exists between the intercanine distance and the difference of the intercommisural and intercanine distances (r=−0.4)

Conclusion

The study showed no relationship between intercanine distance, interincisal distance, lower facial height, and the height of the participants with the intercommissural distance. Hence, intercommissural distance may not be used in marking canine line during bite registration procedure. At best, 1.75–2.45 cm should be subtracted from the intercommissural distance to determine the intercanine distance.  相似文献   
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Purpose

This study was designed to examine the feasibility of combining lymphoscintigraphy and intraoperative sentinel node identification in patients with head and neck melanoma by using a hybrid protein colloid that is both radioactive and fluorescent.

Methods

Eleven patients scheduled for sentinel node biopsy in the head and neck region were studied. Approximately 5?h before surgery, the hybrid nanocolloid labeled with indocyanine green (ICG) and technetium-99m (99mTc) was injected intradermally in four deposits around the scar of the primary melanoma excision. Subsequent lymphoscintigraphy and single photon emission computed tomography with computed tomography (SPECT/CT) were performed to identify the sentinel nodes preoperatively. In the operating room, patent blue dye was injected in 7 of the 11 patients. Intraoperatively, sentinel nodes were acoustically localized with a gamma ray detection probe and visualized by using patent blue dye and/or fluorescence-based tracing with a dedicated near-infrared light camera. A portable gamma camera was used before and after sentinel node excision to confirm excision of all sentinel nodes.

Results

A total of 27 sentinel nodes were preoperatively identified on the lymphoscintigraphy and SPECT/CT images. All sentinel nodes could be localized intraoperatively. In the seven patients in whom blue dye was used, 43% of the sentinel nodes stained blue, whereas all were fluorescent. The portable gamma camera identified additional sentinel nodes in two patients. Ex vivo, all radioactive lymph nodes were fluorescent and vice versa, indicating the stability of the hybrid tracer.

Conclusions

ICG?C99mTc-nanocolloid allows for preoperative sentinel node visualization and concomitant intraoperative radio- and fluorescence guidance to the same sentinel nodes in head and neck melanoma patients.  相似文献   
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Background

Literature abounds linking one’s job to certain unpalatable health outcomes. Since exposures to hazardous conditions in industrial environments often results in sundry health effects among workers, we embarked on this study to investigate the hepatic health effects of occupational activities in the petroleum refining and distribution industry.

Method

Biochemical markers of liver functions were assayed in plasma, using Reflotron dry chemistry spectrophotometric system. The study was conducted on randomly selected workers of Port Harcourt Refining Company (PHRC) and Pipelines and Petroleum Product Marketing Company (PPMC) both in Alesa-Eleme near Port Harcourt, Nigeria, as well as non-oil work civil servants serving as control subjects.

Result and conclusion

Results showed that, bilirubin ranged 0.3-1.6 mg/dl with a mean of 0.66±0.20mg/dl among the oil workers as against 0.5-1.00mg/dl with a mean of 0.58±0.13mg/dl in non-oil workers, Alkaline phosphatase ranged 50.00-296.00u/l (mean: 126.21±39.49u/l) in oil workers as against 40.20-111u/l (mean: 66.83±18.54u/l) for non-oil workers, Aspartic transaminases (AST) ranged 5.80-140.20u/l (mean: 21.81±11.49u/l) in oil workers against 18.00-44.00u/l (mean: 26.89±6.99u/l) for non-oil workers, while Alanine transaminases (ALT) ranged 4.90-86.00u/l (mean: 22.14±11.28u/l) in oil workers as against 10.00-86.60u/l (mean: 22.30±10.22u/l) for the non-oil workers. A close study of the results revealed that although the mean values for all the studied parameters were still within the parametric reference ranges, however, relative to the referents, there were significant increases (P<0.05) in plasma bilirubin (though anicteric) and alkaline phosphatase that was not matched with a corresponding increase in the plasma transaminases, suggesting a possibility that toxic anicteric hepatoxicity is part of the potential health effects of sundry exposures in the Nigeria petroleum oil refining and distribution industry. Gender differentiation data showed that though the mean values for the parameters were higher in males than females, the increases were not significant in most cases (P>0.05), whereas data for age and exposure period classifications revealed that irrespective of the age of the worker, the effects are likely to start after the first five years, manifesting fully after the first decade of occupational exposures. Thus, an update of industrial/occupational health measures is necessary for a safer and healthier work environment.  相似文献   
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BACKGROUND: The therapeutic value of immediate completion lymph node dissection (CLND) for sentinel node (SN)-positive melanoma is unknown. The aim of this study was to evaluate the impact of immediate CLND on the outcome of patients with SN-positive melanoma. METHODS: Patients with SN metastases treated between 1993 and 2008 at ten cancer centres from the European Organization for Research and Treatment of Cancer Melanoma Group were included in this retrospective study. Maximum tumour size, intranodal location and penetrative depth of SN metastases were measured. Outcome in those who had CLND was compared with that in patients who did not undergo completion lymphadenectomy. RESULTS: Of 1174 patients with SN-positive melanoma, 1113 (94·8 per cent) underwent CLND and 61 (5·2 per cent) did not. Median follow-up for the two groups was 34 and 48 months respectively. In univariable survival analysis, CLND did not significantly influence disease-specific survival (hazard ratio (HR) 0·89, 95 per cent confidence interval 0·58 to 1·37; P = 0·600). However, patients who did not undergo CLND had more favourable prognostic factors. Matched-pair analysis, with matching for age, Breslow thickness, tumour ulceration and SN tumour burden, showed that CLND had no influence on survival (HR 0·86, 0·46 to 1·61; P = 0·640). After adjusting for prognostic factors in multivariable survival analyses, no difference in survival was found. CONCLUSION: In these two cohorts of patients with SN-positive melanoma and prognostic heterogeneity, outcome was not influenced by CLND. Copyright ? 2012 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.  相似文献   
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In migraine, headache severity varies with age. As a consequence, the effectiveness of medication may also depend on a patient's age. The purpose of this study was to assess the combined effect of age and drug treatment on headache characteristics. Using data from clinical trials of sumatriptan in adolescents and adults, we show how the interaction between age and drug exposure can be parameterised as a covariate on a Markov model that describes the decline of headache severity over three clinically defined stages (no relief, relief and pain-free status). The model explains important clinical observations: (i) the rates at which the pain relief and pain-free status were attained were found to be inversely related to age; (ii) in placebo-treated patients, the mean transit time from 'no relief' to 'relief' is 3 h for young adolescents and increases to 6 h for patients aged ≥ 30 years; and (iii) sumatriptan reduces the transit time to 2 h, irrespective of age. These findings indicate that the therapeutic gain over placebo increases with age. Prospective studies of antimigraine drugs should take this relationship into account when extrapolating efficacy data from adults to adolescents.  相似文献   
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