冲顶式上颌窦底提升植骨同期牙种植的实验研究

[目的]探讨用Summer's骨凿冲顶提升上颌窦底后窦底骨质和黏骨膜改变情况以及种植体与周围组织结合生物学变化,为临床应用该项技术提供进一步可靠的实验依据.[方法]16只狗随机分为提升高度不同(2 mm、4 mm)2组,每只狗植入种植体4枚,一侧植骨,一侧不植骨,在不同时间(3、6、12、24周)取材.标本经大体观察,放射检查,组织学检查,四环素荧光检查,抗BMP-2免疫组化检测.[结果]移植骨愈合良好,种植体形成骨结合,提升4 mm不植骨种植体顶端无骨形成.[结论]上颌窦提升2 mm种植体顶端有骨存在,提升4 mm时,植入种植体顶端多数情况下无骨存在.     

羟基磷灰石眼座植入后暴露原因及其处理

目的：探讨羟基磷灰石眼座植入术后暴露的问题。方法：羟基磷灰石（HA）眼座植入术后暴露者15例，用不同方法进行治疗和观察。结果：眼座暴露多发生在5天-30天之内，暴露范围为2mm-13mm，其中8例自行愈合，7例进行手术处理。结论：HA眼座植入术后主要并发症是眼座暴露，其原因为HA眼座微孔缺乏纤维血管长入，眼座暴露可依其范围，大小采用不同方法处理，暴露范围为中度（≥6mm）以上时，应尽早手术处理。     

种植体深度和加载方向对下颌骨应力分布影响的三维有限元分析

目的分析下颌骨种植体种植深度和加载方向对周围骨组织的应力分布影响，为临床种植应用提供参考。方法CT扫描一位第一磨牙缺失的健康女性下颌骨，运用MIMICS图像重建其几何结构，ADINA建立下颌骨及种植体平齐0mm、高于1mm、低于-1mm骨界面三种有限元模型，分析比较该模型在垂直和颊舌向两种加载方式下周围骨组织内的应力分布。结果两种加载方式下三种模型相比，最大应力出现的部位没有明显变化，但数值发生了很大变化，以低于骨界面-1mm模型数值最大，高于骨界面1mm模型最小。颊舌向与垂直向加载相比，三种模型均呈现颊舌向数值明显高的态势。结论CT扫描最大限度地忠实于个性化的解剖结构，种植体种植深度和加载方向对骨组织内的应力分布有重要影响，本文结果将为临床种植技术提供一定的理论参考。     

硬组织锯割机制作带种植体不脱钙骨磨片的方法研究

目的探讨LeicaSP1600硬组织锯割机制作带种植体不脱钙骨磨片的方法要点及注意事项。方法使用LeicaSP1600硬组织锯割机将常规塑料包埋后的带种植体骨标本沿种植体长轴锯割出厚150～200μm骨片，将其磨至60-80μm厚，行荧光染色观察，再行亚甲兰～酸性品红染色观察。结果制得的带种植体不脱钙骨磨片，光学显微镜和荧光显微镜下能观察到种植体周骨结合情况。结论正确使用LeicaSP1600硬组织锯割机，能较快制作出高质量的带种植体不脱钙骨磨片，可相对延长锯片使用寿命，节省骨标本。     

Influence of a Nanoporous Zirconia Implant Surface of on Cell Viability of Human Osteoblasts

Purpose : The dense nonretentive surface of zirconia implants was modified into a nanoporous surface using selective infiltration etching surface treatment. The aim of this study was to investigate the influence of such a nanoporous modified zirconia surface on the attachment of human osteoblasts. Materials and Methods : Human osteoblasts were cultured for 21 days on (i) selective infiltration etched zirconia (nanoporous surface), (ii) polished zirconia, (iii) polished titanium, or (iv) airborne particle abraded acid etched (SLA) titanium disks. After the culture period the following parameters were assessed: number of cells, the morphology of the cells, the attachment of the cells, alkaline phosphatase activity, and the level of total protein (α= 0.05). Results : Statistical analysis revealed a significantly higher cell count on the third (F = 17.4, p < 0.001) and eighth day (F = 163, p < 0.001) for nanoporous zirconia and SLA titanium surfaces compared to polished specimens. The number of cells (nanoporous zirconia 160 ± 20/mm², SLA titanium 133 ± 15/mm²) and cell size (nanoporous zirconia 50.7 ± 3 μm, SLA titanium 42.5 ± 4 μm) were significantly higher than polished specimens. Nanoporous zirconia specimens demonstrated comparable alkaline phosphatase activity (0.0036 ± 0.0035 ng/μl) and intracellular protein content (72.7 ± 0.9 ng/μl) compared to other tested groups. Scanning electron microscopy revealed that cells attached on the polished surface using finger‐like processes, whereas on the nanoporous surface, finger‐like processes were not observed, as the cell membrane appeared to be in close proximity to the underlying surface. Conclusion : The findings of this study suggest that a nanoporous zirconia surface favors cell growth and attachment compared to a polished surface. It was proposed that a nanoporous zirconia surface may improve clinical performance of zirconia implants.     

Impairment of echocardiographic acoustic window caused by breast implants.

Cosmetic breast implants are increasing in popularity. The presence of a breast implant overlying the anterior mediastinal space as a cause of impairment of the echocardiographic acoustic window has not been described previously. Here, we report three cases with significant impairment of echocardiographic acoustic window caused by breast implants. Clinicians should be aware of this interference and women should be informed of this dilemma before considering this cosmetic surgery.     

全颌种植固定义齿游离臂长度与应力分布关系的研究

全颌种植固定义齿游离臂（ＣＡ）长度的控制一直是临床的研究热点，本研究在建立全下颌种植固定义齿三维各向异性有限元模型的基础上，计算了２００ＮｆＨｅ力垂直加载时种植义齿各组成部分的受力。结果表明：１．全颌种植固定义齿ＣＡ增长可导致义齿各组成部分应力增大，当长度超过１４ｍｍ时，应力增加的幅度更大。２．全颌种植固定义齿游离臂增长对种植体骨界面尤其是末端种植体骨界面的危害最大，其次是末端种植体，但对支架的影     

Fixation of hydroxyapatite‐coated revision implants is improved by the surgical technique of cracking the sclerotic bone rim

Revision joint replacement has poorer outcomes that have been associated with poorer mechanical fixation. We investigate a new bone‐sparing surgical technique that locally cracks the sclerotic bone rim formed during aseptic loosening. We inserted 16 hydroxyapatite‐coated implants bilaterally in the distal femur of eight dogs, using a controlled weight‐bearing experimental model that replicates important features of a typical revision setting. At 8 weeks, a control revision procedure and a crack revision procedure were performed on contralateral implants. The crack procedure used a splined tool to perform a systematic local perforation of the sclerotic bone rim of the revision cavity. After 4 weeks, the hydroxyapatite‐coated implants were evaluated for mechanical fixation by a push‐out test and for tissue distribution by histomorphometry. The cracking revision procedure resulted in significantly improved mechanical fixation, significantly more bone ongrowth and bone volume in the gap, and reduced fibrous tissue compared to the control revision procedure. The study demonstrates that the sclerotic bone rim prevents bone ingrowth and promotes fixation by fibrous tissue. The effect of the cracking technique may be due to improved access to the vascular compartment of the bone. The cracking technique is a simple surgical method that potentially can improve the fixation of revision implants in sclerotic regions important for obtaining the fixation critical for overall implant stability. © 2009 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 996–1001, 2009