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991.
A 67-year-old white man was seen for the treatment of a painful oral ulceration. His medical history was highly suggestive of systemic disease. Radiographs of the chest and cultures of sputum were positive for tuberculosis. The incidence, appearance, and characteristics of oral tubercular lesions have been presented. The diagnosis of tuberculosis should be considered along with carcinoma, syphilis, fungal disease, and trauma whenever granulomatous ulcerations appear in the oral cavity.  相似文献   
992.
The effects of short-term (21 days) and long-term (116 days) treatment with oral diphenylhydantoin (DPH, 6 g/kg diet) on the development of rat teeth was investigated. Long-term DPH reduced the size of the incisors and of all the molars except the upper first. There was also a reduction in tooth weight and both changes were shown to be independent of body weight. Short-term DPH reduced the size of the incisors and upper third and second molars only.The relationship of these lesions to the shortened tooth roots found in epileptics on chronic anticonvulsant therapy and the stunted root development seen in hypoparathyroidism is discussed. It is suggested that DPH may induce a state of “pseudohypoparathyroidism” by inhibiting the action of parathyroid hormone on bone and tooth. This complication would appear to be additional to the so-called “anticonvulsant-induced osteomalacia”.  相似文献   
993.
Comparative study of healing and remodeling in various bones.   总被引:1,自引:0,他引:1  
The effects of normal physiologic stimuli on healing and remodeling in various bones of different embryogenic origin in the rabbit and dog were compared. The findings disclosed that the healing and remodeling of the tibia and mandible were consistent with the magnitude of the forces that act on these bones; namely, the tension created by muscle contraction and the compression exerted by body weight in the tibia, and masticatory compression in the mandible. The slower healing and remodeling in the maxilla was attributed to the selection of the excision of bone in the edentulous site with minimal masticatory compression and muscle-pull tension. The excision of the bone in the skull appeared to heal by fibrous tissue with no evidence of remodeling, which is consistent with the minimal external forces that act on this bone.  相似文献   
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997.
Dentistry is undergoing significant changes with need for the dentist to manage a larger body of knowledge and information. There will be increasing reliance on electronic information systems in education, research, and dental practice. Dental informatics is concerned with computer and information science and technology and communications. Goals, that could be adopted for Australia, were proposed in the USA in 1989. Specific action steps that could meet those goals are proposed for Australia.  相似文献   
998.
The effect of dietary fats such as butter, lard, cottonseed oil, and hydrogenated cottonseed oil on the fatty acid composition of enamel and dentin lipids of rabbit molars was studied. The enamel and dentin of molars of all of the rabbits contained a variety of fatty acids, palmitic, stearic, oliec, linoleic, and eicosapentaenoic being the major ones. Enamal lipids were more unsaturated than dentinal lipids in all of the groups. A significant difference was noticed in the fatty acid composition of both the enamel and dentin between these four groups of rabbits. Linoleic acid content was highest in both the enamel and dentin lipids of rabbits fed cottonseed oil. There was no marked difference in the saturated-unsaturated fatty acid ratio in both the enamel and dentin among rabbits fed cottonseed oil, lard, and butter. It is concluded that tooth lipids are responsive to diets and are in direct equilibrium with dietary components.  相似文献   
999.
Cultures of human gingival fibroblast cells from patients with a positive or negative history of recurrent herpes simplex virus (HSV) infection were compared with respect to susceptibility to HSV infection and interferon activity. There was a possible inverse relationship between interferon sensitivity of gingival fibroblast cells and a clinical history of recurrent disease. No correlation was found between prior infection and other parameters of interferon activity or susceptibility of the cells to HSV.  相似文献   
1000.
The “fused” multiple pontic design, previously described for the mandibular posterior segment, can be used in other parts of the mouth.The interpontic embrasures can be filled in the maxillary anterior segment using pink porcelain to improve the appearance of the fixed partial denture. The pink porcelain may also be used to solve the esthetic problems created by moderate ridge resorption and loss of the papilla between pontic and abutment.Patients with two or more missing maxillary incisors are frequently told that a fixed partial denture cannot achieve the same esthetic result as a removable prosthesis. However, patients can enjoy the advantages of fixed prosthodontics without sacrificing esthetics using the technique of pink porcelain application described.  相似文献   
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