超高分子量聚D,L乳酸小夹板螺钉的组织反应与降解动物实验研究

观察聚乳酸Ｄ,Ｌ聚乳酸小夹板,螺钉植入体内后的组织学反应及降解过程。方法采用自身对照研究,用超高分子量生物降解材料聚Ｄ,Ｌ乳酸制作小夹板,螺钉,对１０只狗进行颧弓骨折内固定,并金属钛小夹板,螺钉内固定相比较,观察聚Ｄ,Ｌ乳酸小夹板,螺钉植入体内后的组织学反降解过程。     

超高分子量聚D,L乳酸小夹板螺钉行颧弓骨折内固定的动物实验研究

目的：观察新型可吸收性骨夹板的骨内固定效果。方法：采用自身对照研究方法,用超高分子量生物降解材料聚Ｄ,Ｌ乳酸制作小夹板、螺钉内固定装置,对１０只狗进行颧弓骨折内固定,并与金属钛小夹板、螺钉内固定相比较。结果：对颧弓凹陷性骨折,分子量高达６０万ｋＤ以上的超高分子量聚Ｄ,Ｌ乳酸小夹板螺钉的机械性能足够维持骨段的稳定性并支撑其愈合。结论：聚Ｄ,Ｌ乳酸小夹板、螺钉同金属钛小夹板、螺钉内固定一样,对颧弓骨折具有良好的骨内固定效果,对骨折愈合过程无任何不良影响,其显著优点是无需二次手术取出。     

超高分子量聚D,L乳酸小夹板螺钉行颧弓骨折内固定的动物实？…

观察新型可吸收性骨夹板的骨内固定效果。方法采用自身对照研究方法,用超高分子量生物降解材料聚Ｄ,Ｌ乳酸制作小夹板,螺钉内固定装置,对１０只狗进行灌弓骨折内固定,并与金属钛小夹板、螺钉内固定相比。结果对颧弓凹陷性骨折,分子量高达６０万ＫＤ以上的超高分子量聚Ｄ,Ｌ     

可吸收DL—聚乳酸夹板行颌面部骨折内固定的实验研究

对ＤＬ－聚乳酸夹板在８只狗的下颌骨，颧弓骨折内固定的疗效，进行了实验研究。采用大体，组织学，四环素荧光活体骨标记，Ｘ线摄片，观察骨折４，８，１２，２８周时的内固定效果；ＰＤＬＬＡ板的组织相容性及其在体内的降解，并与微型钢板内固定比较。     

可吸收DL－聚乳酸夹板行颌面部骨折内固定的实验研究

对ＤＬ－聚乳酸（ＰＤＬＬＡ）夹板在８只狗的下颌骨、颧弓骨折内固定的疗效，进行了实验研究。采用大体、组织学、四环素荧光活体骨标记、Ｘ线摄片，观察骨折４，８，１２，２８周时的内固定效果；ＰＤＬＬＡ板的组织相容性及其在体内的降解，并与微型钢折内固定比较。结果表明：１．超高分子ＰＤＬＬＡ板具有良好的力学性能，在下颌体、颧弓骨折内固定中可获得良好固位，达到与微型钢板相同的内固定效果。２．ＰＤＬＬＡ板具有良好的组织相容性，不引起周围组织的炎症和异物反应。３．ＰＤＬＬＡ板植入后脆性逐渐增加，术后３月仍呈原有外形，但重量下降，术后７月已降解为碎片和小颗粒，重量丧失７０％以上，但何时完全吸收有待更远期观察。     

生物降解性骨内固定夹板行颧弓骨折内固定的实验研究

目的：研究ＤＬ－聚乳酸（ＰＤＬＬＡ）夹板行颧弓骨折内固定的疗效及材料生物和物理性能。方法：选用４只狗造成颧弓骨折后用ＰＤＬＬＡ夹板内固定，采用大体、组织学、四环素荧光活体骨标记、Ｘ线摄片，观察骨折内固定效果；并与微型钢板内固定比较。结果：①ＰＤＬＬＡ板具有良好的力学性能，在颧弓骨折内固定中可达到与微型钢板相同的内固定效果。②ＰＤＬＬＡ板具有良好的组织相容性，不引起周围组织的炎症和异物反应。③ＰＤＬＬＡ板植入后逐渐降解，何时完全吸收有待更远期观察。结论：ＰＤＬＬＡ是一种很有应用价值，比较理想的骨折内固定生物材料。     

聚D,L乳酸螺钉复合骨形成蛋白行骨折内固定的实验研究

目的　观察聚D,L乳酸螺钉复合骨形成蛋白(rhBMP-2)植入骨组织后对钉道骨缺损及周围骨折愈合的作用。方法　采用自身对照研究,将聚D,L乳酸与rhBMP-2复合后附着于聚D,L乳酸螺钉凹槽内,植入固定4 只犬的下颌颏部骨折,并与聚D,L乳酸螺钉对照。术后4、8、12、16周取标本行X线和组织学观察。结果　实验侧复合螺钉钉道骨缺损及周围骨折处的成骨程度明显比对照侧强;骨折断端固定愈合良好。结论　聚D,L乳酸复合 rhBMP-2螺钉对钉道骨缺损及周围骨折愈合具有明显促进作用,对骨折愈合能起到良好的固定作用。     

L/DL-聚乳酸夹板行下颌骨骨折内固定的实验研究

目的　观察国产新型L/DL 聚乳酸与DL 聚乳酸接骨装置行骨折内固定的效果 ,并比较两种可吸收材料的性能。方法　用L/DL 聚乳酸及DL 聚乳酸接骨板、螺钉固定 16只狗下颌骨骨折 ,作同体对照研究。采用大体、组织学、X线摄片、骨力学测试及材料理化性能检测等方法 ,观察 2、4、8、2 0周时的内固定效果及材料降解吸收情况。结果　所有狗双侧下颌骨骨折皆在对位良好的情况下愈合。L/DL 聚乳酸夹板固定侧骨力学强度在 4、8周时高于DL 聚乳酸夹板固定侧 (P <0 .0 5 )。L/DL 聚乳酸的降解吸收较DL 聚乳酸慢 ,对机械强度的保持优于DL 聚乳酸。结论　L/DL 聚乳酸及DL 聚乳酸接骨板、螺钉均能保证下颌骨骨折的愈合 ,符合骨折内固定的生物力学原则。L/DL 聚乳酸有较高的机械强度 ,更适合于向小型化发展。     

国产消旋聚乳酸接骨板体内降解过程观察

目的探讨国产消旋聚乳酸（ＰＤＬＬＡ）接骨板在动物体内的降解过程和影响因素。方法运用国产ＰＤＬＬＡ接骨板行犬下颌骨体部人工骨折内固定,并在股部埋植ＰＤＬＬＡ接骨板作为对照。观察不同时期下颌骨体部骨折区和股部埋植区国产ＰＤＬＬＡ接骨板大体降解情况、骨折愈合情况以及完整的接骨板表面扫描电镜观察结果的变化情况。结果植入前国产ＰＤＬＬＡ接骨板表面光滑,消旋聚乳酸分子间结合紧密;随着时间的推移,植入的ＰＤＬＬＡ接骨板表面降解痕迹逐渐明显,消旋聚乳酸分子间的降解孔隙和密度逐步增大,而且骨折区ＰＤＬＬＡ接骨板的降解速度比股部埋植区更快;骨折愈合情况良好。结论国产ＰＤＬＬＡ接骨板能够在体内逐步自行降解吸收;其降解过程与骨折的愈合过程相吻合,并能够促使骨折早期愈合     

新型骨组织工程支架复合BMP-2体内异位成骨的研究

目的 评价新型骨组织工程支架聚消旋乳酸与聚乳酸-聚乙二醇-聚乳酸共混物复合rhBMP-2作为组织因子载体的体内异位成骨的能力.方法 在12只成年新西兰兔背部两侧骶棘肌内各制作互不相通的2个肌袋.然后将复合rhBMP-2的材料植入一侧肌袋为实验组,未复合rhBMP-2的材料作为对照组植入另一侧肌袋.术后2、 4、 8周取材行大体标本观察、组织学观察,观察体内异位成骨情况.结果 植入体内8周,实验组见成熟骨组织形成,对照组无骨组织形成.结论 新型骨组织工程支架复合rhBMP-2后植入动物体内有较强的异位成骨能力,是BMP的良好载体.     

Mood and malignancy: head and neck cancer and depression

Head and neck cancer patients have been reported to show high rates of depression. However, it is important to differentiate between depressive symptoms and a depressive disorder. This review critically examines the relationship between head and neck cancer and depression. There appears to be little evidence for depression leading to an increased risk of developing cancer and although depressive symptoms in head and neck cancer patients are common, very few studies have investigated depressive disorders. The studies that investigated the incidence of a comorbid depressive disorder report a prevalence very close to that of the general population, implying that major depression is not a normal response to cancer. Finally, the evidence suggests that comorbidity of depression with cancer has a negative impact on morbidity and mortality. Both psychosocial and biological factors could account for this. Dysregulation of the stress hormone axis and increased inflammation are common in depressive disorders and have been suggested as underlying pathological mechanisms and are both markers of poor prognosis in cancer. This evidence suggests that a relatively small number of patients develop a depressive disorder following a diagnosis of cancer, but for those that do it may have a substantial impact on their prognosis.     

低氧和自噬与肿瘤的发生发展

自噬作为真核生物的一种应激调控机制,既可以促进肿瘤的发生发展,又可以抑制肿瘤的增殖。在肿瘤局部低氧的微环境下,低氧诱导因子-1α、哺乳动物雷帕霉素靶蛋白信号转导通路抑制、内质网应激均可促进自噬的发生。在肿瘤快速地发生发展过程中,肿瘤的糖代谢功能增强、活性氧族增多、窖蛋白1下调以及上皮间质转化的激活均诱导了自噬的发生并促进肿瘤的局部浸润、侵袭转移和耐药,因此,抑制自噬可能为肿瘤治疗提供一种新的策略。     

Survey of Australian and New Zealand Oral and Maxillofacial Surgery trainees and recent specialists--education and experience

This study examined the demographic characteristics, educational background and attitudes toward training of all recent OMS specialists and all current trainees in Australia and New Zealand in 1996. The early nineties is a key period as it marks the transition from an essentially dentally based speciality (85% dental degree in 1990); to recent specialists with an increasing number with both medical and dental degrees (33% dual degree 1990-1996); to predominantly dual degree training (84.4% dual in 1996). Current trainees had more extensive experience in pathology, preprosthetic and reconstructive surgery. They were also strongly critical of the length and cost of training.     

Open bite and and therapeutic strategy

Anterior open bites can be divided into two categories: skeletal and dento-alveolar. The etiology, basically affecting dento-alveolar structures, is functional or mechanical such as the rotation of the first higher molars, the exaggerated curve of Spee and the incisor supraclusion and the simple orthodontic treatment can bring a therapeutic success but functional rehabilitation remains the guaranty of such a stability of our treatment. The purpose of this work is to make a teaching article which puts the point on the interest of the elements of the diagnosis and the orthodontic treatment indicated in certain clinical situations of anterior open-bite; this by detailing biomechanics of correction of this anomaly requiring various therapeutic strategies. Functional rehabilitation remains always the guaranty of such a therapeutic stability. For the teaching aspect, we want to attach stereotypic forms and also to present clinical cases treated in the service of consultation and dental treatment in order to answer such a request.