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91.
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   
92.
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   
93.
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95.
下颌复合组织移植实验的显微外科解剖学基础研究   总被引:1,自引:0,他引:1  
同种异体下颌区复合器官和组织移植的研究刚刚起步,为了了解下颌区复合器官和组织移植的显微外科解剖基础,在犬、兔和猴进行了下颌区及颈部血管解剖比较研究。结果发现,在下颌区域,颌外动脉、颌内动脉、颌外静脉和颌内静脉形成闭合的循环回路。在此基础上可以确定下颌复合器官移植的范围并使移植手术得以进行。  相似文献   
96.
填料含量对牙科光固化粘结剂残余单体量的影响   总被引:1,自引:0,他引:1  
目的:探讨填料的加入对牙科光固化粘结剂聚合转化度的影响。方法:采用高效液相色谱仪测试了不同填料含量的光固化粘结剂固化后的残余单体量。结果:无填料粘接剂残余单体量最大,随填料含量增加而减少;照射60s,9.1%组显示最小。结论:填料含量5%(wt),照射60s较适宜  相似文献   
97.
非调和型正畸粘接剂的粘接强度考察   总被引:2,自引:0,他引:2  
采用一种自制的非调和型正畸粘接剂,考察了牙釉质与正畸托槽在五种实验条件下的粘接抗张强度。结果表明该粘接剂不需调和,操作时间充裕,具有足够的初始粘接强度和长期粘接强度,其平均粘接抗张强度大于7MPa,特别适用于对多个正畸附件的粘接。  相似文献   
98.
99.
多孔TiNi合金牙种植材料的制备及性能检测   总被引:2,自引:1,他引:2  
目的 制备多孔TiNi合金牙种植材料,为该合金进一步进行动物实验及临床应用提供实验依据.方法 采用添加氢化钛和碳酸氢铵做为造孔剂,模压成型(200 MPa),真空烧结.对烧结后的试样进行XRD物相分析、显微观测以及能谱分析.结果 XRD物相分析表明,Ti-Ni合金试样中主要有TiNi、Ti2Ni、TiNi3三相.在烧结工艺相同的情况下,钛含量不同的试样孔隙的数量、大小、均匀程度都相差不多.结论 TiNi合金种植体制备成三维多孔结构是可行的.  相似文献   
100.

Objective

The literature suggests that females have less adverse effects to infection than males, due to the protective effects of oestrogen. The purpose of our study is to compare the systemic effects of induced periapical lesions between groups of animals with various serum concentrations of oestrogen.

Methods

To induce periapical inflammation, two molar tooth pulps were exposed in ovariectomized (OVX) and normal female (F) and castrated (Cast-M) and normal male (M) Sprague–Dawley rats (Experimental group, E). Sham-operated control animals from each group were also studied (Control group, C). Twenty-eight days later, serum and maxillas were collected. Serum 17β-oestradiol, testosterone, MMP-9, IL-18, IL-6, TNF-α, and IL-1β concentrations were measured by ELISA. Maxillas were cleaned of residual tissue and digital radiographs were made to verify the presence of periapical lesions. Data were compared by factorial ANOVA, post hoc Tukey, and Pearson correlation tests. Groups were considered to be significantly different when p < 0.05.

Results

The serum concentration of IL-18, TNF-α, IL-1-β, IL-6 and MMP-9 was greatest in OVX-E animals, compared to all other groups (p < 0.001). F-E rats had significantly higher serum concentrations of these cytokines, compared to F-C. The fold difference in serum concentration of the biomarkers (between E and C groups) was significantly greater in females than males, even though males had higher baseline concentrations of all these biomarkers.

Conclusion

When females are oestrogen-deficient, their systemic response to periapical lesions is significantly greater than males, suggesting that oestrogen is essential in protecting females from the effects of this type of inflammation.  相似文献   
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