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81.

Objective

To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non‐OLP group), and subjects without oral mucosal lesions (control group).

Material and methods

Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non‐OLP lesions (28 patients), and healthy subjects (32 subjects).

Results

There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (= 0.03) and non‐OLP (= 0.02) groups. Low SFR was not a factor for colonization by Candida spp.

Conclusions

Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme.  相似文献   
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There is much discussion in the dental literature regarding the superiority of one impression technique over the other using addition silicone impression material. However, there is inadequate information available on the accuracy of different impression techniques using polyether. The purpose of this study was to assess the linear dimensional accuracy of four impression techniques using polyether on a laboratory model that simulates clinical practice. The impression material used was Impregum Soft?, 3 M ESPE and the four impression techniques used were (1) Monophase impression technique using medium body impression material. (2) One step double mix impression technique using heavy body and light body impression materials simultaneously. (3) Two step double mix impression technique using a cellophane spacer (heavy body material used as a preliminary impression to create a wash space with a cellophane spacer, followed by the use of light body material). (4) Matrix impression using a matrix of polyether occlusal registration material. The matrix is loaded with heavy body material followed by a pick-up impression in medium body material. For each technique, thirty impressions were made of a stainless steel master model that contained three complete crown abutment preparations, which were used as the positive control. Accuracy was assessed by measuring eight dimensions (mesiodistal, faciolingual and inter-abutment) on stone dies poured from impressions of the master model. A two-tailed t test was carried out to test the significance in difference of the distances between the master model and the stone models. One way analysis of variance (ANOVA) was used for multiple group comparison followed by the Bonferroni’s test for pair wise comparison. The accuracy was tested at α = 0.05. In general, polyether impression material produced stone dies that were smaller except for the dies produced from the one step double mix impression technique. The ANOVA revealed a highly significant difference for each dimension measured (except for the inter-abutment distance between the first and the second die) between any two groups of stone models obtained from the four impression techniques. Pair wise comparison for each measurement did not reveal any significant difference (except for the faciolingual distance of the third die) between the casts produced using the two step double mix impression technique and the matrix impression system. The two step double mix impression technique produced stone dies that showed the least dimensional variation. During fabrication of a cast restoration, laboratory procedures should not only compensate for the cement thickness, but also for the increase or decrease in die dimensions.  相似文献   
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Discoid lupus erythematosus is a manifestation of chronic cutaneous lupus erythematosus with a small risk of systemic involvement. In this review article, the role of predisposing factors such as haplotype, hormones, antibodies and sunlight are discussed. The clinical features, including variants and associations, and management options are presented.  相似文献   
89.
Tinnitus is distressing and affects the quality of life for many patients. Because primary care physicians may be the entry point for patients seeking help for tinnitus, we urge them to acknowledge this symptom and its potential negative impact on the patient's health and quality of life. Physicians should actively listen to the patient and provide hope and encouragement, but also provide realistic expectations about the course of treatment. The patient must also understand that there may be no singular "cure" for tinnitus and that management may involve multidisciplinary assessment and treatment.  相似文献   
90.
Studies by light microscopy on synovium obtained from 11 patients with Reiter's syndrome during the first month of an episode showed proliferation of synovial lining cells, polymorphonuclear neutrophils among the synovial lining cells, increased surface fibrin, and vascular congestion. Biopsy specimens taken later showed vascular congestion and still proliferated synovial lining cells, fewer polymorphonuclear neutrophils in some, and a tendency toward increased infiltration with lymphocytes and plasma cells. Electron microscopy of samples from 8 patients during the first month of disease activity showed occlusion of vessels by platelets in 4, and fibrin or dense granular material in the vessel walls in 4. Five of the patients with arthritis of less than 4 weeks duration had unidentified intracellular and extracellular particles; some of these were highly suggestive of Chlamydia. No such particles were noted in samples from patients with more chronic cases. Using an antibody to Chlamydia trachomatis and the peroxidase-antiperoxidase technique, immunocytochemistry showed reaction product in synovial macrophages in 2 patients with arthritis of less than 4 weeks duration, but not in the 1 patient studied who had more chronic disease. These studies provide support for dramatic synovial vascular injury consistent with that caused by endotoxin and the presence of chlamydial antigen in synovial macrophages, at least in the early phases of synovitis.  相似文献   
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