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91.
92.
Oral Radiology - To evaluate the feasibility, safety, and efficacy of endovascular interventions in the emergent management of life-threatening hemorrhage associated with head and neck neoplasm....  相似文献   
93.
人牙周膜细胞中内源性骨形成蛋白的流式细胞仪分析   总被引:4,自引:0,他引:4  
目的:定量检测和分析人牙周膜细胞(PDLC)表达内源性骨形成蛋白(BMP)的情况。方法:应用BMP单克隆抗体,通过流式细胞仪和免疫组化ABC的方法双重判定。结果:在离体培养的人PDLC中有一半左右的细胞能表达BMP。结论:牙周膜细胞具有一定的合成和分泌BMP的能力;可以进一步认为人的牙周膜细胞是具有成骨潜能的,在牙周组织再生中有积极作用。  相似文献   
94.
目的:评估自行研制用于引导牙周组织再生(GTR)的双抗胶原膜(BACM)在临床应用中实际抗菌能力和抗酶解性能。方法:对12例牙周炎患者行体内药物释放试验,以高效液相色谱测其龈沟液四环素含量;应用扫描电镜观察GTR术后1周取出的BACM膜上的细菌附着情况。结果:牙周袋内放置四环素150μg,1周后龈沟液中药物浓度为20.78μg/ml,扫描电镜观察胶原膜纤维结构完好无损,BACM上细菌数明显少于对照膜(GLCM)。结论:临床评估BACM能显著减少细菌对胶原膜的附着,并具有一定抗胶原酶的性能。  相似文献   
95.
Angiographic findings in seventy cases of maxillofacial hemangioma are reported. The tumors have been divided into four types: (1) plexiform hemangioma, (2) cavernous hemangioma with venous drainage, (3) cavernous hemangioma without venous drainage, and (4) the so-called "diffuse type" of cavernous hemangioma. The angiographic features of the four types are described, and clinical application is evaluated. The angiograms demonstrate the location, extent, blood supply, and drainage of the tumors and show whether they communicate intracranially, thus providing valuable criteria for planning and determining the mode of treatment.  相似文献   
96.
OBJECTIVES: To investigate the effectiveness of two restorative materials for reinforcing thin-walled roots and their microtensile bond strengths to root canal dentin. METHODS: Twenty-one decoronated maxillary central incisor roots were root filled and the canals enlarged to leave approximately 1.0 mm thick dentin walls. The roots were distributed randomly to three equal groups. Group 1 (control): a large tapered cast post-core was fabricated. Group 2 (BIS-CORE): a thick layer of dual-cured composite was placed in the post-hole before fabrication of a small-diameter tapered cast post-core. Group 3 (ChemFil Superior): a thick layer of glass-ionomer was placed, as before. Metal-ceramic crowns were fabricated for all teeth. Microtensile bond strength tests and optical and atomic force microscope observations were employed to examine adhesion between the two restorative materials and the root canal dentin. RESULTS: Mechanical loading (kN) demonstrated that composite 0.64 (S.D. 0.05), but not glass-ionomer 0.49 (0.05), significantly reinforced the fracture resistance of thin-walled roots, P<0.001. Microtensile bond strengths (MPa) were 21.7 (1.6) for composite and 12.9 (1.7) for glass-ionomer, P=002. SIGNIFICANCE: A thick intermediate layer of resin-bonded composite, sandwiched between the root dentin and a small-diameter cast Ni-Cr post or dowel, increased significantly the fracture resistance of the roots.  相似文献   
97.
98.
OBJECTIVE: To establish cephalometric norms of McNamara's analysis in young Chinese and compare them to those of a matched young Caucasian sample. MATERIALS AND METHODS: The material comprised lateral cephalometric radiographs of a random sample of 200 male and 205 female 12-year-old southern Chinese children, and an additional sample of 43 male and 43 female 12-year-old British Caucasian children in Hong Kong. The radiographs were digitized twice with the CASSOS program. RESULTS: The results showed that there were statistically significant gender differences for six out of the 11 cephalometric variables in the Chinese, but for only one variable in the Caucasians. The size of the statistically significant gender differences varied from -0.3 to 0.4 on SD scores. There were statistically significant ethnic differences for eight variables in males and seven variables in females. The size of the observed statistically significant ethnic differences varied from -1.8 to 1.6 on SD scores. CONCLUSION: The use of specific standards for Chinese, separate for gender, for McNamara's cephalometric analysis seems to be justified.  相似文献   
99.
目的推介一种新的准确评价上下颌骨矢状向关系的头影测量方法:β角.方法β角由A点、B点、髁状突中点三个骨性标志点构成,测量值反应上下颌骨在矢状方向的不调;样本选取137名患者,按照3项标准分三组,分别反应三种错(牙合)类型,并计算均数和标准差.结果安氏Ⅰ类错(牙合)β值为36.42°±3.33,安氏Ⅱ类错(牙合)的β值为26.88°±6.81,安氏Ⅲ类错(牙合)的β值为45.36°±3.68;各组β值在性别上没有显著性差异.结论β角能反应上下颌骨的矢状关系,β值在33°-39°之间为安氏Ⅰ类错(牙合)畸形,安氏Ⅱ类错(牙合)β角较锐,安氏ⅢⅡ类错(牙合)患者的β角较钝.  相似文献   
100.
In Asia, a round face rather is more acceptable than a square face. Intraoral mandibular angle ostectomy is a common aesthetic procedure for correcting a prominent mandibular angle. However, an operation of sheer straight-lined prominent mandibular angle resection would sometimes create extramandibular angles or palpable bone steps in the margin of mandibular body and produce unnatural lower one-third facial appearance, especially for a square and disproportional mandibular angle even extending to the middle mandibular body. This article describes the method of multistage mandibular angle ostectomy to produce a natural lower one-third facial contour. This method mainly focused on the posterior area of mandibular ostectomy by intraoral approach, although it has modifications. Mandibular contouring is realized first through bone cutting from antegonial notch posteriorly upperward, reaching to the middle ramus of the mandible near the earlobe; second ostectomy followed along mandible lower part is to get rid of extramandibular angle according to the preoperative design; sometimes necessarily, third ostectomy creates a smooth mandibular contour. From January 2000 to January 2010, 379 patients were operated on, and satisfactory results were achieved. Thus, this procedure could avoid excessive bone cutting, extramandibular angles, unnatural appearance, and palpable bone steps.  相似文献   
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