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Objective. The aim of this study was to determine the feasibility of a novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride as a viable alternative to infiltration anesthesia in dentistry.Study design. The study was carried out in three stages. First, the drug delivery system (DDS) was subjectively evaluated for adherence to the gingival mucosa and peak effect of anesthesia. In the second stage, a comparative subjective and objective evaluation of the DDS with a marketed topical gel preparation was carried out. Finally an open label, nonblinded clinical trial was carried out using the exodontia model. A total of 49 extractions were attempted in 41 patients. The effect of the following variables was investigated in the study: (1) jaw (maxillary and mandibular), (2) overall mobility, (3) position-notation of tooth (1, 2, 3, 4…). The positive extractions were statistically analyzed by the t test comparison of means of two independent variables.Results. Subjective evaluation revealed that the DDS adheres to the gingiva within a minute and produces peak effect in 15 minutes. Comparative study revealed that the DDS produces greater depth of anesthesia than the marketed topical gel. Of 49 extractions attempted with the DDS, 40 were successful, giving an efficacy of 81.63%.Conclusion. The novel saliva-activated bioadhesive drug delivery system of lidocaine hydrochloride exhibits potential as a feasible alternative to infiltration anesthesia in dentistry.  相似文献   
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Exfoliative cytology is a rapid, non-invasive procedure for assessing dysplastic change within the oral epithelium. The indications for oral exfoliative cytology are reviewed and a technique for cell collection and smear examination is presented. The value of exfoliative cytology in oral cancer screening programmes as a public health measure is discussed.  相似文献   
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The loss of maxillary central incisors at an early age has psychological, esthetic, and functional implications. Multiple treatment options are available for replacing missing central incisors. The management demands a multidisciplinary approach involving the orthodontist, prosthodontist, and periodontist. Treatment planning requires consideration of a variety of clinical and nonclinical factors. This clinical report attempts to demonstrate different strategies for the management of unilaterally and bilaterally missing central incisors.  相似文献   
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This paper reports on a survey of the coverage of health issues in relation to older people, on district nurse and health visitor courses. The evidence suggests that only limited coverage is given to issues which affect those in the age group 45 65 years. It is suggested that this group should become an important target for health education in the community. The implications of this for nurse educators are explored.  相似文献   
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The degree of stenosis in the carotid artery can be predicted using automated carotid lumen diameter (LD) measured from B-mode ultrasound images. Systolic velocity-based methods for measurement of LD are subjective. With the advancement of high resolution imaging, image-based methods have started to emerge. However, they require robust image analysis for accurate LD measurement. This paper presents two different algorithms for automated segmentation of the lumen borders in carotid ultrasound images. Both algorithms are modeled as a two stage process. Stage one consists of a global-based model using scale-space framework for the extraction of the region of interest. This stage is common to both algorithms. Stage two is modeled using a local-based strategy that extracts the lumen interfaces. At this stage, the algorithm-1 is modeled as a region-based strategy using a classification framework, whereas the algorithm-2 is modeled as a boundary-based approach that uses the level set framework. Two sets of databases (DB), Japan DB (JDB) (202 patients, 404 images) and Hong Kong DB (HKDB) (50 patients, 300 images) were used in this study. Two trained neuroradiologists performed manual LD tracings. The mean automated LD measured was 6.35 ± 0.95 mm for JDB and 6.20 ± 1.35 mm for HKDB. The precision-of-merit was: 97.4 % and 98.0 % w.r.t to two manual tracings for JDB and 99.7 % and 97.9 % w.r.t to two manual tracings for HKDB. Statistical tests such as ANOVA, Chi-Squared, T-test, and Mann-Whitney test were conducted to show the stability and reliability of the automated techniques.  相似文献   
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