Contemporary management of lateral root perforation diagnosed with the aid of dental computed tomography

Lateral root perforation unnoticed during post-space preparation, and followed by post cementation, can subsequently be challenging to diagnose in the labio-lingual plane due to the two-dimensional nature of conventional radiography. This paper demonstrates the application of a recently developed three-dimensional imaging system, cone beam computed tomography, in the diagnosis of iatrogenic root perforation. A clinical case is reported where labial post perforation in a maxillary central incisor occurring 15 years previously presented with a sinus tract and radiolucent lesion. Non-surgical retreatment and perforation repair using mineral trioxide aggregate was performed with the aid of an operating microscope. The sinus tract resolved with radiographic evidence of healing at 1-year recall.     

两种口腔镍铬合金离子析出的体外实验研究

目的 研究Heraenium S与TILITE P两种口腔镍铬合金在唾液pH值和成分变化时离子析出行为。方法 将两种合金试件在pH6墙正常唾液环境中浸泡一周，再用pH4的酸性及酸性加0．1％F^-的人工唾液处理两小时，之后回到正常唾液环境中浸泡一周，观察其在处理前、后镍离子的析出和表面理化状态的改变。结果 ①在正常唾液环境中HeraeniumS合金镍离子的析出量大于TILITEP合金；②pH降低和氟化物的加入增大了两种合金镍离子的析出量，其中TILITEP合金大于HeraeniumS合金；③在短暂的pH降低和加入氟化物后再回到正常唾液环境中，TILITEP合金的镍离子析出量大于HeraeniumS合金；并且在合金表面可以观察到形态学上的腐蚀破坏。结论 口腔镍铬合金的镍离子析出受到口腔环境动态变化的影响，TILITEP合金对环境改变的敏感性曼大。     

Carnoy液对金黄地鼠颊囊作用的研究

目的了解Carnoy液对粘膜组织损伤的性质，为其用于临床治疗提供理论依据。方法以金黄地鼠颊囊作为模型，以Carnoy液作为涂布试剂，药液作用时间为4min，于术后不同时期处死动物，切取标本，进行光镜和透射电镜观察。结果Carnoy液可引起颊囊粘膜上皮坏死脱落，溃疡形成，穿透深度约0.3mm。术后第3周坏死区上度重新形成，胶原纤维及成纤维细胞明显增多。结论Carnoy液是一种烧灼性质较强的物质，将其用于上皮性囊肿治疗，可因上皮破坏而治愈囊肿或降低其复发率。     

下颌复合组织移植实验的显微外科解剖学基础研究

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。     

Dentofacial features of a family with Crouzon syndrome. Case reports

Crouzon syndrome is an autosomal dominant condition characterized by craniosynostosis with associated dentofacial anomalies. This paper describes the variable clinical features in affected individuals over two generations of a family with particular reference to the dentofacial deformities and discussion of management strategies.     

A histochemical study of the effects of high doses of sodium fluoride on dipeptidyl peptidase II activity in the rat incisor ameloblast

Female Wistar rats, 3 weeks old, were given sodium fluoride in saline solution (isotonic) by intraperitoneal injection at a dose of either 0, 10 or 20 mg per kg body weight. This treatment was given 9 times over 4.5 days. After fixation by perfusion and demineralization in neutral EDTA, hemi-mandibles were sectioned in a cryostat. Sections were stained for dipeptidyl peptidase II activity, using the specific substrate Lys-Ala-MNA and the coupler Fast Blue B for histochemical localization. Staining indicative of dipeptidyl peptidase II was found in the enamel organ of the incisor, particularly in cells of the stratum intermedium and in both secretory and maturation ameloblasts. This staining was markedly reduced in ameloblasts of rats given either 10 or 20 mg sodium fluoride per kg body weight.     

Metastases to lingual lymph nodes from squamous cell carcinoma of the tongue

The diagnosis of squamous cell carcinoma (SCC) of the tongue metastasising to the lingual lymph nodes is rare. Until now lingual lymph nodes have not been mentioned in any system of lymph node classification. We report a case of SCC of the tongue with metastases to the lymph nodes in the superficial floor of the mouth, and to levels I and II lymph nodes. We provide evidence of the existence of lingual lymph nodes, and validate the practice of removing the lymph node-bearing-tissue of the floor of the mouth during neck dissection in cancers of the oral cavity.     

倾斜基牙的牙周应力分析及修复方法的研究进展

临床修复工作中,近缺隙侧倾斜牙齿常被选作基牙,倾斜基牙所受!力是非轴向力,容易造成牙周组织损伤,如何更加合理有效地利用倾斜基牙进行修复是临床亟待解决的问题。本文就倾斜基牙的牙周应力分析及修复方法作一综述。     

局部应用二磷酸盐对鼠正畸牙移动影响的研究

目的 探讨局部注射Zoledronate溶液对鼠正畸牙齿移动距离与牙周组织形态的影响。方法 选用42只雄性Wistar大鼠，牵引其上颌第一磨牙近中移动。实验中分别将Zoledronate溶液及生理盐水注射入实验组（左侧）及对照组大鼠（双侧）上颌第一磨牙腭侧的粘骨膜下。注射于实验前3d开始，共进行9次，每3d一次。分别在加力0、3、7、14、21d后记录上颌第一磨牙移动距离，组织HE染色后，观察牙周组织形态学的改变。结果 ①实验组大鼠牙齿移动距离明显低于对照组。②实验组大鼠压力侧破骨细胞数在实验全过程中均低于对照组，而根分叉区破牙骨质细胞数除加力14d外，2组差异无显著性。③实验过程中Zoledronate溶液对破骨细胞和破牙骨质细胞以外的细胞作用不明显。结论 Zoledronate能有效地抑制支抗牙移动，减少压力侧牙槽骨表面破骨细胞数。