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981.
A clinical trial was performed to examine the effect of ACDEMIN, a combination of lysozyme chloride and vitamins (manufactured by Grelan Pharmaceutical Co., Ltd.,; supplied by Takeda Chemical Industries, Ltd.). The subjects were 65 patients with slight to moderate symptoms associated with locally developed diseases including gingivitis, periodontitis, pericoronitis of the wisdom tooth and gingival abscess. Improvement of the condition was evaluated according to symptom on the basis of local findings examined prior to and 7 days after administration. Adverse effects were also evaluated in terms of discomfort. General improvement was determined on the basis of improvement in symptoms and general safety on the basis of a comprehensive assessment of the adverse effects. The usefulness of the drug was determined on the basis of general improvement and general safety as assessed above. The results were as follows: 1) Of the 65 patients who entered the trial, 62 completed the course of administration. 2) The rates of improvement ("slightly improved" or better) according to symptom were 65.6% for gingival inflammation, 40.0% for bleeding, 50.0% for pus discharge, 41.8% for swelling, 61.9% for local pain, 26.7% for mouth odor, 21.7% for color tone and 62.3% for discomfort. 3) The rates of usefulness ("slightly useful" or better) according to disease were 66.7% for gingivitis, 92.0% for periodontitis, 81.8% for pericoronitis of the wisdom tooth and 100.0% for gingival abscess. 4) The usefulness of the drug was graded "very useful" in 4 patients, "fairly useful" in 18, "slightly useful" in 31 and "not useful" in none, with an overall rate of usefulness of 85.5% ("faily useful" or better). 5) No patients presented symptoms indicating an adverse effect.  相似文献   
982.
Increased information on dentistry in the mass media in recent years may have caused changes in patients' attitudes toward dental care. To better understand patient' attitudes, we conducted a questionnaire survey of patients on the first visit to our hospital. Of 384 responses, 196 were eligible for statistical analysis. The following findings were obtained. 1. Among the motives for visiting a dental clinic, "Manifestation of pain or symptoms" was given by majority (85.7%) of respondents, followed by "detection of abnormality" (20.4%). The percentage of patients wanting treatment of "any part suggested by the dentist" was highest (35.7%), followed by those expecting "treatment including cleaning" (30.1%). The above results indicate that patients still tend to visit a clinical after subjective symptoms appear and leave the content of treatment to the dentist. However, an increasing number of patients appear to be concerned with their oral condition and visit a clinic before manifestation of symptoms. 2. Among factors in selecting their dentist, "expertise" obtained the highest percentage, 87.2%, followed by "providing prompt treatment" (38.8%) and "trying to avoid pain" (32.1%), in that order. Dissatisfaction with dentists was described as "no explanation of treatment" in 57.1%, "lack of sympathetic attitude" in 38.3% and "easily resorts to tooth extraction" in 35.4%. These results suggest that patients expect good human relations with their dentists, sufficient explanations of treatments and sympathetic consideration, as well as expertise. 3. The majority of patients (85.7%) hoped to receive instructions on oral hygiene and to be increased interest in information above prophylaxis. Meeting their needs will remain a future issue for dentists.  相似文献   
983.
Sixty-seven per cent of the forty-three patients suffering from craniomandibular disorders (CMD) had a vertical condylar asymmetry greater than 3%. After division into two different groups, myogenous and arthrogenous origin of pain, it was found that myogenous patients were younger and showed significantly bigger asymmetry between the vertical heights of the left and right condyles, evaluated on an Orthopantomogram, than the patients with arthrogenous origin of pain (P less than 0.05). The mean vertical condylar asymmetry was 9.10% and 4.83%, respectively. It is suggested that the possible triggering morphological condylar asymmetry on the pathogenesis of a CMD should be recognized at an early stage of the disorders development. The use of a screening protocol and an Orthopantomogram could be of preventive importance in daily practice.  相似文献   
984.
A study was conducted to determine whether the wear resistance of a posterior composite could be improved by maximizing filler particle-to-particle contacts. This was expected to reduce stress concentrations on the resin matrix and thus reduce occlusal wear. A self-curing quartz-filled composite with this design, P-10, was used to restore 90 Class I and II cavity preparations in adult teeth. Restorations were recalled after baseline at six months, one year, two years, and three years to measure wear by direct and indirect evaluation methods. There was no apparent advantage for this material compared with other previously evaluated posterior composites. The average cumulative wear for P-10 after three years was 145 microns. In addition, the restorations were evaluated for color-matching, interfacial staining, secondary caries, marginal adaptation, surface texture, and postoperative sensitivity. This material was not significantly different in those ways from other posterior composite products except in terms of more rapid color change, because it is self-cured.  相似文献   
985.
The purpose of this experiment was to clarify the characteristic changes of vasculature in edentulous alveolar mucosa and the effect of wearing a complete denture during sleep. Thermal stimulations were applied to the oral mucosa of five normal subjects and five completely edentulous patients and the responses of blood vessels were observed using both Impedance Plethysmography (IMP) and Reflection Photoelectric Plethysmography (RPP). Quantitative comparisons were made between edentulous patients and dentulous normal subjects, and between patients wearing complete dentures during sleep and those who do not. The following results were obtained. 1) The responses of blood vessels were divided into four groups. Type 1 showed dilatation in IMP and RPP. Type 2 showed dilatation but had late initial rising in IMP. Type 3 showed initial contraction in either or both IMP and RPP, and followed by dilatation few seconds later. Type 4 showed no changes in RPP but dilatation in IMP. 2) There was definite difference between edentulous and dentulous subjects in the frequency of exhibition of each type. Especially for the edentulous patients type 4 was observed in all stimulation temperature. 3) For the dentulous subjects there were more cases showing responses of RPP in digital apex than those do not. This was most conspicuous at the 50 degrees C stimulation. However for the edentulous patients there were about equal number of each cases. 4) The responses of blood vessels for both dentulous and edentulous subjects became greater and blood volume increased both with time at each temperature and as the stimulation temperature were raised. However the increase in the response was greater for the edentulous patients when the stimulation temperature was raised from 0 degrees C to 50 degrees C. 5) The responses of blood vessels became greater after two weeks when complete dentures were worn during sleep at night. And when dentures were not worn during sleep the responses decreased to a level lower than what it used to be after three weeks. 6) From the above results it was suggested that oral mucosa of the edentulous patients were losing their sensitivity due to wearing complete dentures and were not receiving as much effect of the contractile control from body as the dentulous subjects. It was also suggested that wearing denture during sleep at night cause inflammation of oral mucosa and increase the metabolism of tissue in edentulous patients.  相似文献   
986.
Initial calcification in human dental pulp has been studied with electron microscopy in 20 human teeth over a period of 21 days following pulp exposure and capping with autogenous dentin fragments. Five days after operation, dentin fragments were surrounded by degeneration cells and inflammatory cells. Occasionally a macrophage that had phagocytosed a dentin fragments was observed. Fourteen days after operation, osmiophilic needle-like crystalline structures were found in spherical bodies in the collagen fibrils or on the dentin surface. Ca and P were detected in these needle-like crystalline structures by energy dispersive X-ray analysis. They tended to increase in size and to fuse together to form mineralizing globules with the passage of time. Initial calcification around the dentin fragments developed various patterns, including spherical bodies in the collagen fibrils and direct apposition of needle-like crystals on the dentin fragments.  相似文献   
987.
Forty-four patients with oral cancer were examined by ultrasonography to detect cervical lymph nodal metastases. The lymph nodes, which were histopathologically or clinically confirmed to have cancer metastases, showed the following characteristic echogram findings: distinctive nodal boundary, posterior echo enhancement and an increased ratio of the shortest and the longest diameters of the node. It is suggested that these three peculiar ultrasonographic findings are considered to be important items for the differential diagnosis of benign nodes from the cervical metastasis of oral cancer.  相似文献   
988.
989.
990.
Langerhans cells (LC) are cell types found in the skin and gingiva. LC have immunological functions as phagocytic cells and as antigen-presenting cells for T and B lymphocytes. Sections from biopsies of the gingiva in cases of periodontal disease were found to have increased numbers of LC. These biopsies also contained intragingival bacteria. Serial sections of frozen specimens of human gingiva were prepared for staining. Hematoxylin and eosin were used for tissue survey, the Gram stain for assessment of bacterial invasion, anti-Leu-6 monoclonal antibody associated with peroxidase technique (PAP) to identify LC, antibacterial sera to Bacteroides gingivalis and Actinobacillus actinomycetemcomitans associated with peroxidase to specifically identify these two common periodontopathogenic bacteria. Additional positive identification of bacteria was performed by preparing the same histological section containing gram-stained particles for scanning electron microscope and transmission electron microscope LC confirmation. The results suggest that the increased number of LC seen in diseased sites of oral epithelium containing intragingival microorganisms may be one of the host immune mechanisms to penetration by bacteria.  相似文献   
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