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991.
Aplastic anemia is a failure of all the cellular components of the bone marrow and, untreated, usually results in death from bleeding and/or infection within 4 months. Treatment by bone marrow transplantation offers the only means of survival. When a bone marrow graft fails, the patient is extremely susceptible to severe infection and/or hemorrhage. In this case, a bone marrow transplantation in a 34-year-old white man with aplastic anemia failed. Among the medical problems that subsequently developed were severe, prolonged and life-threatening oral bleeding and infection.  相似文献   
992.
Ten patients undergoing treatment with bridges supported by osseo-integrated oral titanium implants were studied regarding the oral microflora. Saliva samples for microbiological studies were collected before the abutment operation, 1 week after the operation, after the bridges were inserted and again 52 weeks after the abutment operation. The implants did not induce colonization with "plaque streptococci" such as Streptococcus mutans and Streptococcus sanguis. A marked colonization with potentially pathogenic microorganisms such as Staphylococcus aureus, Pseudomonas species and enterobacteria was observed after the abutment operation. This was probably due to the use of surgical dressing.  相似文献   
993.
Three composite resin systems, one conventional (Concise) and two microfilled (IsoPast and Silar), used with and without an intermediate resin (Concise Enamel Bond), were evaluated with and without thermal stress for in vitro retentive strength and sealing ability to acid-etched human enamel. All three materials yielded significantly different shear strength values. The use of an intermediate resin significantly improved both the shear strength and resistance to microleakage of Silar, while no differences were observed for Concise and IsoPast. The thermocycling procedure did not generally or consistently affect the results. The failure mode of the three acid-etched composite resins was studied by evaluation of the failure surface and by describing the percentage of enamel, composite, and interface which were present. The use of an intermediate resin did not significantly influence the failure mode, and the correlation between the failure mode and retentive strength, although significant was low. The study confirmed the importance of adequate wetting action of a resin on the etched enamel to ensure proper bonding.  相似文献   
994.
Patients undergoing cancer chemotherapy often suffer from oral complications as a result of their disease and its treatment. The effects of the chemotherapy on the bone marrow and oral mucosa, coupled with the patient's immunosuppressed state and altered oral microbial flora, predispose these patients to oral mucositis, infection, and hemorrhage. The oral mucosa appears to mirror the effects of the chemotherapy on the bone marrow, as there appears to be a direct relationship between the changing peripheral blood counts and the status of the oral mucosa.  相似文献   
995.
An upper anterior sectional denture is described which consists of (1) a cast cobalt-chromium framework with two passive clasps that contact undercuts on the distal surfaces of the most posterior remaining teeth and (2) a labial flange that carries the replaced tooth or teeth and engages the labiointerproximal gingival undercuts of the anterior teeth adjacent to the edentulous ridge. The cast framework is inserted occlusogingivally, and the labial flange is inserted labiolingually. Both sections are held together by the frictional resistance of the split post of the framework that fits into a tube on the labial flange and hollowed-out artificial tooth. With this type of prosthesis, certain clinical problems can be handled without abutment tooth preparation and with a minimal amount of chair time.  相似文献   
996.
997.
A 48-year-old woman underwent root canal treatment of the upper left lateral incisor and lower right second premolar. Close to the conclusion of the endodontic treatment she complained about headaches. Later on, because of aggravation of her condition, with headaches, fever, malaise, weakness, and numbness of the right limbs, she was admitted to the hospital. The disease progressed to an epileptic state, with appearance of a right hemiparesis. A brain scan and carotid arteriogram revealed the presence of a mass occupying the left parietal space. Craniotomy disclosed an abscess containing yellow pus from which Streptococcus viridans was cultured. After thorough surgical cleansing of the area, removal of the bone for decompression, and treatment with ampicillin the patient improved gradually and slowly regained the mobility of her right side.  相似文献   
998.
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   
999.
Subapical osteotomy of the anterior mandible was carried out on 10 adult Macaca Irus monkeys with and without open bite. Teeth were extracted at 8 weeks, 12 weeks, 24 weeks and 1 year after surgery and the pulps examined histologically. No normal pulps were found. Progressive fibrosis and calcification was noted in all teeth. Patent pulp blood vessels were found up to 24 weeks after surgery. Pulp damage to teeth distal to the osteotomy site was found in 50% of cases. Control teeth extracted from the opposing jaw at the same intervals were all found to have normal pulps.  相似文献   
1000.
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