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131.
132.
目的研究创伤对家兔颞下颌关节滑膜和软骨的影响。方法采用实验性创伤动物模型,透射电镜下观察创伤后颞下颌关节滑膜和软骨的超微结构特征。结果髁突软骨表层结构破损,软骨层不同程度的软骨细胞变性、坏死。滑膜内膜层滑膜细胞变性,胞质内可见大量的空泡和近胞膜处的小泡,微丝增多、密集;细胞膜上可见微绒毛突起;内膜下层出现类“蚓状小体”结构;并首次描述了滑膜内膜层滑膜细胞之间的点粘连连接方式。结论创伤确实可以导致颞下颌关节的退行性改变。 相似文献
133.
STATEMENT OF PROBLEM: Densely sintered aluminum oxide veneered with feldspathic porcelain seems to be a promising technology for the fabrication of porcelain laminate veneers, which provide both strength and esthetics. To effectively use this approach for porcelain veneers, practitioners should know how the resulting color is affected by adding a layer of veneering porcelain onto the aluminum oxide. PURPOSE: This study compared changes in CIE L*a*b* color coordinates of simulated stained teeth when covered with the aluminum oxide core disks alone and after the disks had been veneered with 3 different shades of porcelain. MATERIAL AND METHODS: Fifteen aluminum oxide disks were divided into 3 groups. Each of 5 disks was veneered with porcelain of the Vita shades A1, A2, and B4, respectively. The colors of the substrate covered with the nonveneered disks and the veneered disks were measured separately, and the color differences were calculated. Measurements of the disks on a white background were also performed and used as controls. The extracted data were compared with Vita shade values available from the literature. RESULTS: Statistically significant differences in color coordinates of dark substrates were recorded between the substrate covered by an aluminum oxide disk and the addition of veneering porcelain to the aluminum oxide disks. Veneering the aluminum oxide disks with A1, A2, and B4 porcelain produced significant differences in the resulting color when placed on a dark substrate. The direction of the color modifications correlated with values obtained from the literature. The resulting color was also affected by the color of the underlying structures. CONCLUSION: Although aluminum oxide alone does have a degree of masking capability, the resulting color of porcelain veneers with the use of this material can successfully be modified with the veneering porcelain. 相似文献
134.
The purpose of this review is to describe the training of dental professionals and to give an overview of the oral health care system in Mainland China. It may be of interest and importance for American readers to become aware that there are alternative practice structures and the world is getting smaller. 相似文献
135.
口腔肿瘤患者手术后早期应用肠内营养的临床观察 总被引:1,自引:0,他引:1
目的观察口腔肿瘤手术后早期应用肠内营养对患者营养状况的影响。方法选择口腔肿瘤患者60例,随机分为早期肠内营养(earlyenteralnutrition,EEN)组和传统肠内营养(traditionenteralnutrition,TEN)组,每组30例。EEN组手术后12~16h给予能全力行营养支持,TEN组于肠道排气后经口进食。分别测定术前及术后营养相关指标。结果EEN组术后住院天数及术后8d体质量、氮平衡、血浆白蛋白、前白蛋白、视黄醇结合蛋白和淋巴细胞总数等均明显优于TEN(P<0.05)。结论口腔肿瘤患者手术后早期应用肠内营养,能较好的满足患者的营养需求,可改善术后营养状况。 相似文献
136.
目的 介绍自行研制的带控制阀种植牙手术骨粉收集器,并观察其临床应用效果.方法 选取2008年5月至2009年10月38例牙种植患者,应用自制的骨粉收集器收集种植窝制备时产生的骨碎屑,并将其用于修复种植体周围骨缺损,其中开窗式骨缺损29处,唇颊(舌)侧种植体颈部角形缺损23处.结果 所有病例术后均无创口感染及裂开,原缺损处局部形态饱满,牙龈无明显退缩,X线片示种植体与周围牙槽骨形成良好的骨结合.结论 应用自制骨粉收集器收集的骨粉修复种植体周围小型骨缺损效果良好,使用方便,具有良好的应用前景.Abstract: Objective To introduce a self-developed bone collector designed by the authors and evaluate its effect in clinical application. Methods A self-developed bone collector was used in 38 patients who underwent the dental implant operation from May 2008 to October 2009. During the operation the bone particles were harvested, which was used for the reconstruction of the bone defects around the implant simultaneously. The defects were fenestrate in 29 regions and triangle in 23 regions on buccal or lingual side of the dental implants. Results All cases had no surgical wound infection and dehiscence 7-10 days after operation. Three to six months after implantation, the X-ray showed that all the dental implants had perfect osseointergration and the alveolar bone were successfully augmented. Conclusions Bone debris harvested by self-developed bone collector could repair small peri-implant bone defects, which is simple to use in clinic. 相似文献
137.
目的利用三维有限元模型研究种植体螺纹的旋转角度和密度对种植体初期稳定性的影响。方法建立即刻负载的5种种植体三维有限元模型(0.8mm、1.6mm和2.4mm螺距单螺纹种植体以及双螺纹和三螺纹种植体),进行垂直和水平加载,分析5种种植体颈部和根部的相对位移。结果在3种不同螺距的单螺纹种植体中,垂直加载时0.8mm螺距单螺纹种植体颈部和根部的综合相对位移最小(分别为1.600μm和1.199μm),2.4mm螺距单螺纹种植体颈部和根部的综合相对位移最大(分别为2.451μm和2.019μm);在螺纹密度相同、旋转角度不同的3种种植体中,0.8mm螺距单螺纹种植体颈部和根部的综合相对位移最小,三螺纹种植体颈部和根部的综合相对位移最大(分别为1.994μm和1.602μm);在螺纹旋转角度相同、密度不同的种植体中,双螺纹种植体颈部和根部的综合相对位移(分别为1.913μm和1.495μm)均比1.6mm螺距单螺纹种植体(分别为2.412μm和1.799μm)小,三螺纹种植体颈部和根部的综合相对位移均比2.4mm螺距单螺纹种植体小。结论随着种植体螺纹螺距的增加,种植体对抗垂直载荷的能力减弱;随着种植体螺纹旋转角度的增加,种植体对抗垂直载荷的能力减弱;随着种植体螺纹密度增加,种植体对抗垂直载荷的能力增加。 相似文献
138.
Multiple odontogenic keratocysts (OKCs) are principle features of nevoid basal cell carcinoma syndrome (NBCCS; Gorlin-Goltz syndrome). NBCCS is a genetic disorder transmitted by an autosomal dominant gene with variable expressivity, which is important to recognize when a patient has multiple OKCs. The cysts of the jaws are among the most common findings. Another feature is a certain appearance of the face, such as: large calvaria, high-arched eyebrows, broad nasal root, and mild hypertelorism. Before-therapy diagnosis is, therefore, as important as after-therapy diagnosis. Genetic counseling and examination may also be indicated. The purpose of this paper was to present a family case report of nevoid basal cell carcinoma syndrome with multiple odontogenic keratocysts. The features identified by these combined clinical, imaging, and histologic findings are described, along with a brief mention of the family history and a review of the literature. 相似文献
139.
G Zhang 《中华口腔医学杂志》1990,25(6):337-9, 382-3
It has been well known that the sarcomas of jaw are very vascularized, but reports on the angiography of jaw sarcomas were very few. Based on the preoperative angiography of 3 cases of jaw bone sarcomas and arteriography of their specimens, it has been noticed that the supplying arteries of the mandible ramus sarcoma can be directly from the external carotid arteries; and the supplying arteries can be from inferior alveolar artery in sarcomas of the body of mandible. The tumors are more vascularized than the surrounding normal tissues, and the direction of the arteries can be from central to peripheral in the tumors, which are different from the long bone sarcomas. The vascularization and the retarded blood flow in the tumor are the significant anatomic bases for local perfusion chemotherapy of jaw sarcomas. 相似文献
140.