骨密度测量在评估骨支架材料促成骨作用中的意义

目的:用预制型无机诱导因子复合性骨组织工程支架材料对实验山羊的下颌骨角部大型箱状缺损施行骨重建再造,应用骨密度测量来评估支架材料在组织工程构建骨修复中的价值。方法:15只雌性山羊按每组5只以4、8、12周时间点分为3组,手术制备30 mm×25 mm×10 mm大型箱状缺损,左侧置支架材料,右侧空白对照。分别于4、8、12周处死1组5只山羊,行骨密度的双能X线吸收法(DXA)和X线光密度法(XBMD)检测。结果:DXA和XBMD检测,实验侧和对照侧间差异有统计学意义(P<0.05),和正常骨组间差异无显著性(P>0.05)。结论:实验侧的骨密度系数呈递增式上升,证明本支架材料在组织工程骨构建中的骨诱导作用。对照侧的骨密度系数维持较低水平,提示自发性成骨现象欠佳,在12周前的骨缺损区尚未明显出现自我修复痕迹。骨密度测量可作为术后动态监测组织工程化骨构建存活与否的指标之一。     

无机活性元素组织工程支架材料重建修复山羊颌骨缺损的扫描电镜观察

目的:用扫描电镜观察无机活性元素组织工程支架材料构建的组织工程骨及其修复羊大面积颌骨缺损的体内成骨状况.方法:实验组对15只山羊下颌角缺损(30 mm×25 mm×10 mm大小)以支架材料修复,左侧为实验组,右侧为空白对照组,术后分别于1、3、6个月处死5只动物行扫描电镜及生物化学检查,观察无机活性元素组织工程支架材料体内成骨情况.结果:实验组骨缺损新生骨在1、3、6个月显著优于对照组,空白对照组6个月骨缺损区均无明显骨修复现象.结论:应用扫描电镜观察到无机活性元素组织工程支架材料具有优良的成骨效果.     

无机诱导因子复合性支架材料修复骨缺损的组织学观察

目的:应用无机诱导因子复合性支架材料修复山羊的下颌骨角部大型箱状缺损,研究该材料的成骨性能,探讨其在骨组织工程中的应用价值。方法:山羊15只,按4、8、12周3个时间点分为3组,于双侧下颌角手术制备30mm×25mm×10mm的大型箱状缺损,采用自身配对设计,左侧置入支架材料(A组),右侧空白对照(B组)。术后4、8、12周分别处死动物,取缺损修复区和材料—骨界面标本,观察组织动态学。结果:!4～12周A组有进行性成骨、钙化、骨髓形成的过程,而B组骨缺损内为未充满的纤维结缔组织,下缘有不成熟的软骨细胞附着。结论:支架材料有相当良好的生物活性;修复骨缺损显示优良的修复效果;具有临床应用的可行性。     

羟基磷灰石-凝胶支架复合成骨细胞修复兔颅骨缺损的影像学评价

目的：探索羟基磷灰石/凝胶支架（HAP-GEL）复合成骨细胞在兔颅骨缺损中的修复效果。方法：将HAP-GEL复合物与成骨细胞联合培养,制备兔颅顶骨骨缺损模型,根据植入材料分为3组,分别为HAP-GEL复合成骨细胞、HAP-GEL支架与空白对照。于术后12周通过大体标本观察、X线与CT分析骨缺损修复情况。结果：术后12周影像学评估,空白对照组骨缺损均为明显透射影;HAP-GEL支架复合成骨细胞与HAP-GEL支架组均为低密度影,缺损的边缘略显模糊。结论：HAP-GEL复合成骨细胞修复兔颅骨缺损,可取得较好的修复效果。     

应用预制型无机诱导因子复合性工程支架材料行山羊组织工程化骨构建的放射性核素显像监测

目的探讨预制型无机诱导因子复合性工程支架材料在骨大型缺损中的修复能力,及放射性核素显像技术在此过程中的应用价值。方法实验山羊15只按第4、8、12周时间点分为3组。采用自身配对设计,左侧置入支架材料,右侧空白对照。术后4、8、12周分别通过放射性核素99mTc-MDP骨显像进行监测。结果放射性核素骨显像中感兴趣区(ROI)计数和摄取比值显示:对照组在3个时间点均未见明显核浓聚性的再血管化及明显成骨现象,而实验组则随时间呈单驼峰状,在8周时达峰值,而到12周时血管化已完成,转为以成骨为主,故出现ROI和摄取比值的轻度下降趋势。结论99mTc-MDP监测到新生骨的良好成骨效能和再血管化状况,是一种较好的骨组织工程构建骨的监测手段。     

骨髓间充质干细胞定向诱导分化成骨细胞移植修复腭裂骨缺损

目的：探讨骨髓间充质干细胞（MSCs）定向诱导分化成骨细胞修复先天性腭裂骨缺损的可行性。方法：将16只2月龄的日本大耳白兔,在其腭部制作骨组织缺损和采集胫骨MSCs培养,并随机分为2组。实验组：将骨髓间充质干细胞扩增后复合明胶海绵支架并行成骨细胞定向诱导分化后,植入腭骨缺损区;对照组：进行与实验组相同的手术操作,腭骨缺损区仅植入明胶海绵支架。于4、6、8和12周采集标本行大体观察、X线片观察等。结果：实验组4周时骨缺损部分有骨痂形成,第6周时实验组骨缺损表面有较多骨痴形成,与骨端连接紧密,有骨桥形成;第8、12周时实验组骨缺损完全修复。对照组骨缺损未见骨组织修复。结论：通过MSCs扩增并向成骨细胞定向诱导分化后,以明胶海绵支架为载体移植腭骨缺损中,能较好的修复骨组织缺损。     

新型骨支架复合材料修复牙槽骨缺损研究

目的:探讨多孔聚丙烯晴基碳纤维/壳聚糖/双相磷酸钙/聚乳酸-羟基乙酸(PAN/CS/BCP/PLGA)复合支架对大白兔牙槽骨缺损的修复能力。方法:采用真空冷冻干燥技术制备多孔PAN/CS/BCP/PLGA复合支架。选取32只成年雄性新西兰大白兔,随机分为实验组和对照组,手术制备大小为10mm×10mm×10mm牙槽骨缺损区。实验组骨缺损区植入PAN/CS/BCP/PLGA复合支架,对照组植入CS/PLGA复合材料,术后2、4、8、12周分期取材,进行X线检查、组织学观察、扫描电镜(SEM)检测和成骨细胞计数分析。结果:术后12周实验组检测结果,X线观察:骨缺损区阻射影与自体骨相同。组织学观察:骨缺损区完全被新骨充填,且为较成熟的板层骨,与自体骨完全融合。SEM检测:骨-材料界面形成骨性结合,移植材料大部分降解,被成熟骨组织替代。成骨细胞计数分析:成骨细胞生长活跃,统计学有显著性差异。结论:多孔PAN/CS/BCP/PLGA复合支架具备良好的生物活性和生物可降解性,对骨缺损的修复能力要优于CS/PLGA复合材料,为其成为骨组织工程支架替代材料提供理论依据。     

载辛伐他汀纳米羟基磷灰石支架材料对兔下颌骨缺损修复的影响

目的:采用骨髓间充质干细胞(BMSCs)复合辛伐他汀支架材料修复兔下颌骨局部缺损,观察辛伐他汀对BMSCs复合支架材料修复兔骨缺损的影响。方法:24只新西兰大白兔随机分为2组,每组12只,制备下颌骨缺损模型。A组为实验组,在缺损区植入复合BMSCs的载辛伐他汀纳米羟基磷灰石支架材料;B组为对照组,植入BMSCs复合羟基磷灰石材料。分别于术后2、4、8、12周处死各组动物,行影像学分析、HE染色、扫描电镜观察等检查。结果:影像学检查及组织学染色结果显示,A组骨缺损处愈合程度、成骨速度及骨质量明显优于B组。扫描电镜显示,A组复合材料与组织相容性好,材料吸收优于B组。统计各组各期牙CT分析数据的骨密度值,结果表明A组的骨密度值明显高于B组(P<0.05)。结论:实验表明经BMSCs复合的辛伐他汀支架材料具有明显的促进成骨能力,可加速骨缺损的修复效果,提高修复质量。     

天然骨无机材料修复颌骨缺损的临床研究

目的:观察天然多孔骨无机材料修复颌骨囊肿术后缺损的临床效果及适用范围。方法:对33例颌骨囊肿 术后缺损(体积≤4.2cm3)的病例随机分成二组,分别用天然多孔骨无机材料充填和血块充填植入颌骨缺损区。术 后随访1个月、3个月、6个月分别X线片动态比较其密度变化。结果:天然骨无机材料充填组1个月后骨密度增 高,3个月后趋近正常骨密度,颌骨缺损区修复速度明显比血块充填组快。结论:天然多孔骨无机材料在骨缺损区 植入时有引导骨再生的作用,对缺损区促进早期形成有功能性的、成熟的骨组织作用,是一种较为理想的修复骨缺 损的材料,适用范围一般为缺损区体积≤4.2cm3。     

n-HA／PA66人工骨板引导修复腭部软组织缺损的动物实验研究

目的:观察纳米羟基磷灰石/聚酰胺(n-HA/PA66)复合人工骨板对羊腭部软组织缺损的引导修复作用。方法:将12只羊分为实验与空白对照两组,于羊硬腭中份做18.0mm×14.0mm矩形黏骨膜缺损和15.0mm×13.0mm矩形骨缺损,实验组在缺损处植入人工骨板封闭骨质缺损,空白对照组不做任何修复。术后通过大体、病理切片观察黏骨膜组织生长情况和新生组织结构。结果:实验组黏骨膜组织沿人工骨表面爬行生长,于6周内完全关闭软组织缺损;空白对照组软硬组织未能自行愈合。结论:n-HA/PA66人工骨板可引导羊腭部黏骨膜沿其生长,自行修复一定大小的软组织缺损,而达到腭部软组织缺损修复重建的目的。     

Oral cancer: molecular technologies for risk assessment and diagnosis

Purpose: The effective biomarkers related to diagnosis, metastasis, drug resistance and irradiation sensitivity of oral cancers will help the pathologist and oncologist to determine the molecular taxonomy diagnosis and design the individualization treatment for the patients with oral cancers.     

Stimulated whole saliva components in children with Down syndrome

The authors report on the components of stimulated whole saliva from children with Down syndrome—including pH, flow rate, sialic acid and protein concentrations, and amylase and peroxidase activity. Saliva samples were collected from 35 children aged 6–10 years. Of the participants, 17 had Down syndrome and 18 did not. To stimulate saliva production, the children chewed a piece of parafilm for 10 minutes before the sample was collected. Soon after collecting the saliva sample, the authors measured pH using a portable pH-meter. Sialic acid levels were determined with a thiobarbituric acid assay. Protein content was determined with Folin's phenol reagent. Amylase was assayed and the authors measured the maltose produced by the breakdown of starch and peroxidase using ortho-dianisidine.
No statistically significant difference was observed in levels of sialic acid (free and total) between the two groups. Protein concentration was about 36% higher in the group with Down syndrome. However, the salivary flow rate, pH, and amylase and peroxidase activities were lower among the children with Down syndrome.     

柠檬精油对牙周致病菌抑制作用及其安全性初步研究

目的:探讨柠檬精油对牙周致病菌的体外抗菌活性及对细胞增殖的影响。方法:采用微量液体稀释法测定柠檬精油对Pg、Fn、Aa、Pi的最小抑菌浓度(minimal inhibitory concentration,MIC)及最小杀菌浓度(minimum bactericidal concentration,MBC);以较低浓度的MIC为标准稀释LEO作为实验组,采用MTT法测定柠檬精油对HUVECs的毒性作用,明确抑菌浓度下LEO的安全性。结果:柠檬精油对牙周主要致病菌均有抑菌作用,Pg、Fn、Aa、Pi的MIC分别是9.0 g/L、4.5 g/L、4.5 g/L、9.0 g/L,Aa、Fn的 MBC是9.0 g/L,Pg、Pi的MBC未测得。1/2MIC、1/20MIC浓度的LEO能够抑制人脐静脉内皮细胞的生长,而低于1/200MIC浓度的LEO则对人脐静脉内皮细胞的生长没有影响,其中1/200MIC浓度的LEO作用明显优于0.02%的CHX。结论:体外环境中,柠檬精油对牙周致病菌Pg、Fn、Aa、Pi具有抗菌活性,低浓度应用对机体相对安全。     

牙髓再生的研究现状

目前,根管治疗术在临床上已得到了广泛的应用并成功的保存了患牙,但其仍有许多术后并发症。随着组织工程技术在口腔领域的应用,构建一种组织工程化牙髓进行牙髓-牙本质复合体的再生治疗成为可能。近年来国内外已有很多关于牙髓再生的研究,并且已经取得了一定成果。本文将对目前国内外牙髓再生的研究进展现状作一综述。     

Computer-assisted planning for maxillofacial prosthodontic rehabilitation

Computerized tomography (CT) planning and the use of CT derived surgical templates for implant placement have shown promise for restoring function within months after surgical reconstruction of acquired post-oncologic defects.     

Effect of Pingyangmycin on human venous malformation endothelial cells

Purpose: Venous malformations are common vascular anomalies with a propensity of the head and neck. Intralesional injection of Pingyangmycin (PYM, bleomycin A5 hydrochloride) is a widely used sclerotherapy method for the treatment of venous malformation.     

Clinical and pathological aspects on some odontogenic tumors

Odontogenic tumors constitute a very diverse group of lesions that reflects the complex processes of odontogenesis. Controversies over their classification/subtyping, terminology and diagnosis have been persisted, which has direct bearings on therapeutic and/or prognostic implications.     

Can you be too old for oral implants? An update on ageing and plasticity in the oro‐facial sensorimotor system

This review focuses on the capacity of the brain for plasticity and the utility and efficacy of oral implants in helping to restore oro‐facial sensorimotor functions, especially in elderly patients. The review first outlines the components of the oro‐facial sensorimotor system which encompasses both oro‐facial tissues and a number of brain regions. One such region is the sensorimotor cortex that controls the activity of the numerous oro‐facial skeletal muscles. These muscles are involved in a number of functions including reflexes and the more complex sensorimotor functions of mastication, swallowing and speech. The review outlines the use by the brain of sensory inputs from oro‐facial receptors in order to provide for exquisite sensorimotor control of the activity of the oro‐facial muscles. It highlights the role in this sensorimotor control played by periodontal mechanoreceptors and their sensory inputs to the brain, and how oral implants in concert with the plastic capacity of the brain may, at least in part, compensate for reduced sensorimotor functioning when teeth are lost. It outlines findings of ageing‐related decrements in oro‐facial sensorimotor functions and control. The changes in oro‐facial tissues and the brain that underlie these ageing‐related functional alterations are also considered, along with adaptive and compensatory processes that utilise the brain's capacity for plasticity. The review also notes the evidence t hat rehabilitation that incorporates adjunctive approaches such as sensorimotor training paradigms in addition to oral prostheses such as implants may enhance these processes and help maintain or facilitate recovery of sensorimotor functioning in the elderly.     

Tumor microenvironment in oral cancer: novel approaches for immunotherapy

Squamous cell carcinoma of the head and neck (SCCHN), which arises from the squamous mucosal epithelium of the oral cavity, pharynx and larynx, is a major health problem in the US and other parts of the world, especially in developing countries.